What is aromatherapy

Aromatherapy also known as aroma therapy, is a natural technique based on the use of essential oils extracted from fresh plants (flowers, herbs, or trees) for a therapeutic purpose to improve physical, mental, and spiritual well-being ¹. French perfumer and chemist, René-Maurice Gattefossé, coined the term “aromatherapie” in 1937 in his book “Gattefossé’s Aromatherapy” which contains early clinical findings for utilizing essential oils for a range of physiological ailments ². Aromatherapy is frequently used as a synonym for essential oil (also known as volatile oils), which means a natural aromatic substance which a plant secretes from its reproductive organs; on the other hand, an essential oil is an extract obtained by distilling an essence. Essential oils are very concentrated. For example, it takes about 220 pounds of lavender flowers to make about 1 pound of essential oil. The aroma of essential oils fades away quickly when left open to air. The substances used in aromatherapy are not fragrances or aromatic mixtures used in the perfume industry but pure essential oils, volatile substances extracted from diverse parts of plants which have curative property. Therefore, not everything which emits a pleasant smell is necessary an essential oil. The essential oils are most often used by inhaling them or by applying a diluted form to the skin. Many essential oils are used in aromatherapy, including those from Roman chamomile, geranium, lavender, tea tree, lemon, ginger, cedarwood, and bergamot. There is moderate confidence that aromatherapy is effective for pain in dysmenorrhea (period pain or menstrual cramps) ³. Aromatherapy is used by patients with cancer to improve quality of life and reduce stress, anxiety, pain, nausea, and vomiting caused by cancer and its treatment. Aromatherapy may be used with other complementary treatments like massage therapy and acupuncture, as well as with standard medical treatments, for symptom management. Scientists have found potential positive effects of aromatherapy for pain in labor or childbirth; blood pressure reduction in those with hypertension; stress, depression, and sleep in patients on hemodialysis; stress in healthy adults; anxiety in perioperative patients undergoing various surgery types; and sleep quality in various populations, with low to moderate confidence in the evidence ³. For essential oils applied topically, there is moderate confidence in the potentially positive effect of tea tree oil for tinea pedis ³. Although essential oils are given orally or internally by aromatherapists in France and Germany, their use is generally limited to inhalation or topical application in the United Kingdom and United States. Nonmedical use of essential oils is common in the flavoring and fragrance industries. Most essential oils have been classified as GRAS (generally recognized as safe), at specified concentration limits, by the U.S. Food and Drug Administration (FDA). The Food and Drug Administration of the United States guidelines classify essential oils as cosmetics because they are not drugs for treating or prevention of disease ⁴. Therefore, aromatherapy essential oils are not regulated by the FDA unless there is a claim for treatment of specific diseases. The FDA protects consumers from false claims and mislabeled products that mislead the public.

The US Consumer Product Safety Commission monitors unsafe products ⁵. The US Consumer Product Safety Commission enforces federal laws to protect consumers against unreasonable injury and death from products ⁶. Sellers need to be aware of descriptions of aromatherapy and consumers need to know that aromatherapy is complementary ⁶.

Essential oils are used every day for their aromatic scents—for example, perfumes, candles, essential oil plug-ins, scented aerosol sprays for the home, fabric softeners for clothes, hair shampoos, and spices to add flavor to food. Essential oils also are used in over-the-counter herbs and added to medications to add a pleasant flavor to bitter medications.

Essential oils must always be diluted in a suitable carrier oil for topical use or massage; blended with soap, oil, or bath dispersant when adding to bath water. Using essential oils undiluted or ‘neat’ on the skin can result in a skin rash, itching, an allergic reaction, and even severe pain. Essential oils should be kept away from children and pets. Some essential oils are contraindicated during pregnancy and breastfeeding; with some health conditions and with exposure to ultraviolet light (sunbathing, tanning beds). Consult a professional aromatherapist for specific safety guidelines before using.

Aromatherapy essential oils

Essential oils are volatile oils that contain the “essence” of an aromatic plant’s fragrance, which have numerous applications in multiple industries such as flavoring ingredients in food, pharmaceutical and cosmetic products ⁷. Essential oils are found in tiny sacs in various parts of the plant – petals, flowers, leaves, needles, rinds, fruits, seeds, stems, bark, woods, resins, roots, rhizomes and grasses. The term, ‘essential’, was derived from ‘quintessence’ meaning ‘the essence or extract of a substance in its purest and most concentrated form’. These extracts represent the ‘essence’, spirit or life force of the plant which is important for its survival. There are many essential oils used in aromatherapy, including those from Roman chamomile, geranium, lavender, tea tree, lemon, ginger, cedarwood, and bergamot. Each plant’s essential oil has a different chemical make-up that affects how it smells, how it is absorbed, and how it affects the body. Essential oils from different plant species contain more than 200 chemical components which are comprised of volatile and non-volatile components. The major chemical components of essential oils include monoterpenes, esters, aldehydes, ketones, alcohols, phenols, and oxides, which are volatile and may produce characteristic odors. Different types of essential oils contain varying amounts of each of these compounds, which are said to give each essential oil its particular fragrance and therapeutic characteristics. Plant species may have different chemovarieties (variations of subspecies that produce essential oils with different chemical compositions, as a result of genetic variation and growth conditions) ⁸. Thus, their essential oils can occur as several chemotypes that differ in chemical composition and may produce different clinical effects. It should be noted that essential oils are distinctly different chemically from (fatty) oils, such as those used as food.

There are a variety of methods used for the extraction of essential oils, with each method exhibiting certain advantages and determining the biological and physicochemical properties of the extracted oils. Conventional methods for extracting essential oils include steam or water distillation from raw plant material ⁷ or cold-press extraction from citrus peel ⁹.

Synthetic odors are often made up of many of the same compounds that are components of the essential oils. These compounds are synthesized and typically combined with other odor-producing chemicals. However, synthetic fragrances frequently contain irritants, such as solvents and propellants, that can trigger sensitivities in some people ¹⁰. Most aromatherapists believe that synthetic fragrances are inferior to essential oils because they lack natural or vital energy; however, this has been contested by odor psychologists and biochemists ¹¹.

The application of essential oils as antibacterial, anticancer, anti-inflammatory and anti-viral agents is due to their effective and efficient properties. However, the types of essential oils used and the ways they are combined vary, depending on the experience and training of the aromatherapist.

Seeds

Three common examples of essential oils that come from seeds from plants are:

1. Cardamom (Ellettaria cardamomum)—the essential oil is from the plant family Zingiberaceae. Uses for this seed oil include an antibacterial, antifungal, antispasmodic, aphrodisiac, digestive stimulant, expectorant, parasympathetic nervous system stimulant, and stimulant, tonic.
2. Black pepper (Piper nigrum) is from the plant family Piperaceae. Uses for this oil include an analgesic, antiseptic, antispasmodic, antitoxic, aphrodisiac, digestive, and circulatory tonic; reducing fever reducing pain; as a rubefacient; and for stimulating.
3. Sweet fennel (Foeniculum vulgare var. dulce) is from the plant family Apiaceae. Uses for this oil include an anti-inflammatory, antibacterial, antifungal, antispasmodic, detoxifier, and digestive and for relieving gas.13

Stems, Leaves, and Needles

There are 7 common examples of essential oils derived from stems, leaves, and needles.

1. Cistus (Cistus ladanifer) is from the plant family Cistaceae. This essential oil comes from stems, twigs, dried leaves, and dried flowers. Uses for this oil include as a cictrisant or for cell regeneration; as an antibacterial, anti-infectious, antimicrobial, astringent, and antiviral agent; as an immunity booster and regulator; as a tonic and support for parasympathetic and central nervous systems; and for wound healing.
2. Eucalyptus is a tree from the plant family Myrtaceae. It also is referred to by many names, such eucalyptus oil, blue gum oil, blue mallee oil, and gully gum oil. The leaves and twigs are used for burns, wounds, nasal congestion, lowering blood glucose, nasal congestion, and asthma and as a tick repellent. It also is used in medications and supplements.
3. Laurel (Laurus nobilis) is from the plant family Lauraceae. This aromatic evergreen scrub is known for its aromatic dark green, glossy leaves. Dried and fresh leaves oil is used as an analgesic, antibacterial, antimicrobial, antiseptic, antispasmodic, and antiviral; for boosting the immune system and calming the nervous system; and as an expectorant and fungicide.
4. Patchouli (Pogostemon cablin) comes from the plant family Lamiaceae that is commonly called the mint or dead needle busy herb. Oil from leaves are used as an antidepressant, anti-inflammatory, antimicrobial, antiviral, aphrodisiac, astringent, deodorant, and digestive; for relieving gas soothing the nervous system; and as a stimulant and tonic.
5. Peppermint (Mentha x piperita L) comes from the plant family Lamiacae in the mint family. Peppermint essential oil is a common flavoring agent in pharmaceuticals, soaps, cosmetics, food, and beverages. This essential is used as an analgesic, antibacterial, anti-inflammatory, antispasmodic, antimicrobial, decongestive, digestive, and expectorant and relieves coughs.
6. Pine (Pinus sylvestris)—pinus edulis is from the plant family Lamiaceae and from the mint family. Pine essential oil is derived from the needles on the pine tree. The scent is known for the uplifting and positive impact on the mood. It is known for treatment of postsurgery nausea and vomiting. Essential pine oil is used as an analgesic, antibacterial, antibiotic, anti-infectious, anti-inflammatory, antifungal, and antimicrobial agent; assisting in opening lungs and air pathways; as an expectorant; and for soothing nerves.
7. Rosemary (Rosmarinus officinalis) is from the plant family Lamiaceae. This aromatic evergreen shrub’s essential oil is derived from leaves, flowers, and stems. This essential oil is known for folk medicine, flavoring food, and herbal tea. Rosemary has been known as a sacred oil. Uses for this essential oil are as an analgesic, anti-inflammatory, anti-infectious, antiseptic, and antispasmodic agent; for breaking up mucus; as a cognitive stimulant, decongestant, expectorant, muscle relaxant (cineole), stimulant, and tonic; and for wound healing (verbenone).14

Petal and Flowers

There are 8 common essential oils derived from petal and flowers.

1. Clary sage (Salivia sclarea) is an herbaceous perennial in the plant family Lamiaceae with a history of petal and flowers used as an herb. The essential oil of clary sage is used in perfumes and muscatel flavoring in wines and liqueur. This essential oil is used as an antidepressant, antifungal, anti-inflammatory, antispasmodic, and aphrodisiac and for calming the nervous system, relaxing the uterus, and stimulating the blood flow.
2. Chamomile (Matricaria chamomilla [Anthemis nobilis]) is in the plant family Asteraceae and is a common name for several daisy-like flowers. Chamomile essential oil from flowers is used in herbal tea and is a popular night herbal tea due to the sedative affect. This essential oil is used for support for the nervous system, inflammation, insomnia, menstrual issues, headaches, and skin concerns.
3. Geranium (Pelargonium x asperum) and rose (Pelargonium graveolent)—this essential oil comes from the plant family Geraniaceae. This perennial plant has a sweet floral scent with uses in high-end perfumes and skin products with essentials oils resulting in young radiant skin. Essential oil from the flowers are used for reducing anxiety, as a sedative, for stimulating relaxation, as aids in symptoms from menstruation, as an anti-inflammatory, and for supporting healthy lymph drainage.
4. Jasmine (Jasminum sambac; Jasminum grandiflorum)—this essential oil is from the plant family Oleaceae. Jasmine is a genus of shrubs and vines in the olive family. Flowers of this bushy strong-scented perennial plant are used for scent and in tea as a base for green and white teas. As an essential oil, jasmine is used as an antidepressant and aphrodisiac, for calming the nervous system, and as a sexual tonic and stimulant.
5. Lavender (Lavandula angustifolia) —this essential oil is in the plant family of Lamiaceae and is a bushy strong-scented perennial plant. Lavender is a popular house décor and frequently used with dried flowers as a complement in weddings. The popular scent is used in balms, salves, and cosmetics. As an essential oil, lavender is used as analgesic, anti-inflammatory, antifungal, and antispasmodic; for calming the nervous system, lowering blood pressure, and reducing anxiety and sensations of pain; as a sedative; and for wound healing.
6. Neroli (Citrus aurantium var. amara)—this essential oil is in the plant family Rutaceae and is from the bitter orange tree. This essential oil from flowers has a rich floral scent and is known as orange blossom oil. Neroli is used in scented products, such as perfumes and lotions. This essential oil is used as an antidepressant, antifungal, anti-inflammatory, antimicrobial, antioxidant, antiparasitic, antiseptic, and aphrodisiac; for calming; and as a digestive, nervous system stimulant, sedative, and tonic.
7. Rose (Rosa damascena; R damascena var. alba)—this essential is from the plant family Lamiaceae and is a flowering shrub known as a rosebush. Rose oil is a powerful rich sweet smell. It is used commonly in perfumery. This essential oil is used as an antibacterial, antidepressant, anti-infectious, anti-inflammatory, antiseptic, antiviral, aphrodisiac, and astringent agent; for calming the nervous system and reducing anxiety; as a sedative; as a sexual, general, and uterine tonic; and for wound healing.
8. Ylang-ylang (Cananga odorata)—this essential oil is from the plant family Annonaceae, or custard apple family. This tropical flower is a yellow-shaped flower that grows on the cananga tree. Oil from ylang-ylang is used in cologne, lotion, food flavoring, and soap. This essential oil elevates the mood. Ylang-ylang essential oil is used as an antidepressant, anti-inflammatory, antiparasitic, antispasmodic, and aphrodisiac; for calming the nervous system and lowering blood pressure; and as a sexual tonic ¹².

Rinds and Fruits

1. Bergamot (Citrus bergamia) is from the plant family Rutaceae. This yellow or green fruit is a hybrid of lemon and bitter orange and has a bitter taste that is more than grapefruit but less than a lemon. The essential oil from the peel or zest of the fruit can cause photosensitivity, with sun exposure causing damage to sun-exposed skin. The essential oil has a citrus fruit smell, with uses in oil perfumes, cosmetics, and scenting food. This essential oil is used as an air purifier, antibacterial, antidepressant, antifungal, anti-inflammatory, and antiviral; for calming; as a deodorant; for digestive regulating (undereating or overeating); for reducing anxiety; as a sedative and tonic; and for wound healing.
2. Lemon (citrus limonum)—this essential oil is fruit from a small evergreen tree. This oil is from the Rutaceae plant family, with the peel of the fruit and pulp used in culinary and noncultural from lemon essential oil, lemon pie for culinary to cleaning products. The distinct sour taste of lemon is a popular essential oil. The essential oil from lemon is used as an antibacterial, anticoagulant, antidepressant, anti-infectious, anti-inflammatory, antiseptic, antiviral, astringent, antioxidant, and antimicrobial agent; as a digestive stimulant, immunity booster, and lymphatic; and for reducing anxiety.
3. Mandarin (Citrus reticulata) —this essential oil is from the Rutaceae plant family. This small citrus tree grows mandarin oranges that are smaller than oranges. A hybrid of the mandarin orange is the tangerine. The mandarin essential oil from peel and rind is sweeter and can be dried for seasoning and used in various food. This essential oil is used as an analgesic, antidepressant, antiseptic, central nervous system tonic, deodorant, digestive tonic, and immunity booster; for reducing reduces anxiety and fevers; and as a sedative.
4. Sweet orange (citrus sinensis)—this essential oil is from the plant family Rutaceae. This sweet citrusy greenish orange fruit oil is from the peel and zest. This oil is used in top perfumes. The leaves are photosensitive but not the fruit. The sweet orange essential oil is used as an analgesic, antidepressant, antibacterial antifungal, antiseptic, antiviral, deodorant, and digestive tonic; for reducing anxiety; as a sedative; for soothing the nervous system; and as a stimulant.
5. Juniper berry (Juniperus communis)—this purple-black berry is a female evergreen cone. This essential oil is from the plant family Cupressaceae, derived from conifers, and often is used as a spice. The essential oil is used as an analgesic, antiseptic, antiseborrheic, anti-inflammatory, antifungal, antiviral, decongestant, and detoxifier and for increasing circulation and reducing fever ¹³.

Woods and Resins

1. Cedarwood (Cedrus atlanticia)—cedarwood is from the plant family Pinaceae and the needles, leaves, bark, and wood are for extracting the essential oil. The evergreen conifers have a soothing woodsy scent. The essential oil is used as an antifungal, antiseptic, and astringent; for breaking up mucus; and as a calmative, insect repellent, lymphatic decongestant, and general tonic.
2. Frankincense (Boswellia carteri)—this essential oil is in the plant family of Burseraceae and is from a Boswellia tree. Resin that is a hardened gumlike material is used in aromatic incense and perfumes. The essential oil is used as an analgesic, antibacterial, antidepressant, anti-infectious, antimicrobial, and astringent agent; for immunity tonic; for reducing anxiety; as a sedative; and for soothing the nervous system and wound healing.
3. Sandalwood (Santalum album)—this essential oil is from the plant family Santalaceae. The oil is extracted from wood, heartwood of the trunk, and sawdust. The essential oil from sandalwood is used in medications, skin beauty treatment, incense sticks, perfumes, mouthwashes, deodorants, and antiseptics. As an essential oil, it is used as an antibacterial, antidepressant, anti-inflammatory, antimicrobial, antiviral, aphrodisiac, and sedative; for soothing the soothes nervous system; and as a general tonic ¹⁴.

Roots and Rhizomes

1. Ginger (Zingiber officinale) is distilled from the rhizome or underground stem of a root of the herb zingiber. Ginger also is known as the oil of empowerment for the feeling of confidence. Ginger root oil is a frequently used spice. In addition, this dried and ugly root is used as an analgesic, antibacterial, antispasmodic, digestive support, immunity harmonizer, and rubefacient (a substance for topical application that produces redness of the skin, by causing dilation of the capillaries and an increase in blood circulation).
2. Vetiver (Vetiveria zizanoides) is derived from the aromatic roots and also called khus oil. It is derived from the vetiver plant that is a clumpy, green grass that can grow 5 feet or more. This essential oil is used as an antiseptic, antispasmodic, anti-inflammatory, digestive stimulant, immunity booster, and sedative, and for skin support and soothing the nervous system ¹⁵.

Grass

1. Lemongrass (Cymbopogon citratus) is an essential oil that comes from the leaves and stalk of the lemongrass plant. This grassy plant is used in cooking and herbal tea. The oil from the grass has a lemony powerful scent and is bright or pale yellow. This essential oil is used as an analgesic, antidepressant, antiviral, immunity booster, and general tonic.
2. Palmarosa (Cymbopogon martinii var. motia) is an essential oil that comes from a tall herbaceous grass and can be called Indian geranium or rose oil. The oil has a sweet citrus lemony scent that has a yellow color ¹⁶.

Aromatherapy benefits

The therapeutic inhalation of essential oils is thought to have physiological and/or psychological benefits ¹⁷. Aromatherapy using essential oil is thought to mediate emotional responses by affecting the neuroendocrine system and autonomic nervous systems ¹⁸. The effects of aromatherapy are theorized to result from the binding of chemical components in the essential oil to receptors in the olfactory bulb, impacting the brain’s emotional center, the limbic system. In addition to the inhalation of essential oils, there are various topical applications that are purported to be beneficial apart from their aromatic qualities, for instance as antibacterial, anti-inflammatory, and analgesic effects. The chemical components of essential oils have been shown to inhibit bacterial and fungal growth ¹⁹. Studies in animals show sedative and stimulant effects of specific essential oils as well as positive effects on behavior and the immune system. Functional imaging studies in humans support the influence of odors on the limbic system and its emotional pathways. Human clinical trials have investigated aromatherapy primarily in the treatment of stress and anxiety in patients with critical illnesses or in other hospitalized patients. Several clinical trials involving patients with cancer have been published.

In addition to topical antibacterial uses ²⁰, aromatherapy has also been proposed for use in wound care ²¹ and to treat a variety of localized symptoms and illnesses such as alopecia, eczema, and pruritus ²². Aromatherapy has also been studied via inhalation for airway reactivity in common cold ²³.

Studies on aromatherapy have examined a variety of other conditions, including the following:

• Sedation and arousal ²⁴
• Startle reflex and reaction time ²⁵
• Psychological states such as mood, anxiety, and general sense of well-being ²⁶
• Psychiatric disorders ²⁷
• Neurologic impairment ²⁸
• Chronic renal failure (chronic hemodialysis patients) ²⁹
• Agitation in patients with dementia ¹⁸
• Smoking withdrawal symptoms ³⁰
• Motion sickness ³¹
• Postoperative nausea ³²
• Nausea and emesis in combination with fatigue, pain, and anxiety in patients in labor ³³
• Pain alone ³⁴
• Pain in combination with other symptoms ²⁶

Published articles have described the use of aromatherapy in specific hospital settings such as cancer wards, hospices, and other areas where patients are critically ill and require palliative care for the following symptoms:

• Pain.
• Nausea.
• Lymphedema ³⁵
• Generalized stress.
• Anxiety ³⁶
• Depression ³⁷

These observational studies provide examples of the clinical uses of aromatherapy, although they are generally not evidence based. Participants have included hospitalized children with HIV ³⁸, homebound patients with terminal disease ³⁹ and hospitalized patients with leukemia ⁴⁰. Aromatherapy has also been used to reduce malodor of necrotic ulcers in cancer patients ⁴¹.

Studies of aromatherapy use with mental health patients have also been conducted ⁴². Most of the resulting articles describe successful incorporation of aromatherapy into the treatment of these patients, although outcomes are clearly subjective.

When essential oil in aromatherapy is inhaled, molecules activate the olfactory, respiratory, gastrointestinal, and/or integumentary systems based on the pathway of activation. These molecules are capable of releasing neurotransmitters, such as endorphins, to trigger a sense of well-being and an analgesic effect ⁴³. There are 2 common pathways triggering a pathophysiologic response to aromatherapy molecules. The most common pathway is inhalation, such as by a diffuser. Activation of olfactory stimulation produces immediate change in parameters for blood pressure, pulse rate, muscle tension, pupil dilation, body temperature, and blood flow.20 , 21 The following summarizes this pathway:

• The olfactory stimulation by aromatherapy travels via nostrils to the olfactory bulb.
• The stimulus then travels to the brain for processing, where the amygdala triggers an emotional response and the hippocampus retrieves and/or forms memories.
• The limbic system interacts with the cerebral cortex, activating thoughts and feelings.
• The inhaled aromatherapy molecules travel to the upper respiratory tract and then to the lower respiratory tract.
• Molecules than travel to the pulmonary blood vessels to the blood stream then to organs and tissues ⁴⁴.
• In summary, the inhaled aromatherapy molecules affect mind, body, and spirit.

The second common pathway is through the skin, such as by a massage, in which molecules are absorbed through the skin. The pathway is summarized:

• The molecules travel to the upper respiratory track and then the lower respiratory tract.
• Molecules then travel to the pulmonary blood vessels, to the blood stream, and then to organs and tissues ⁴³.
• The skin pathway can activate olfactory stimulation and also activates application of scented oil to the skin pathway triggering a mental and physiological response.
• The skin pathway absorption of essential oils can reduce a patient’s perceived stress, enhance healing, and increase communication ⁴³.

Aromatherapy essential oil is being used increasingly in hospitals and other healthcare settings for symptom management for pain, nausea, general well-being, anxiety, depression, stress, and insomnia ⁴⁵, ⁴⁶. For instance, aromatherapy has been used to help manage the behavioral and psychological symptoms of dementia, such as restlessness and aggression, and to improve sleep or for insomnia ⁴⁷, but scientists don’t know whether it’s helpful because little rigorous research has been done on this topic ⁴⁸. Aromatherapy is also sometimes incorporated into massage therapy for various conditions, such as knee pain from osteoarthritis or pain, anxiety ⁴⁹ and other symptoms in people with cancer ⁵⁰. One study of aromatherapy using two contrasting scents, lemon and lavender, in people under stress found that lemon had a positive effect on mood but neither scent affected stress indicators, biochemical markers of immune system changes, or pain control.

Evidence from 171 clinical trials represented by hemodialysis and perioperative patients, dysmenorrhea (period pain or menstrual cramps), labor/childbirth, sleep, anxiety, and depression were the most widely studied conditions and/or populations ³. Aromatherapy interventions were most commonly delivered via inhalation, though the method of application varied widely. Systematic reviews of aromatherapy frequently included trials of aromatherapy-massage, which may involve direct dermal exposure through the addition of essential oil to massage lotion or oil or may be diffused in the room during massage. There is moderate-confidence evidence that inhaled essential oils are beneficial for pain in dysmenorrhea ³. Inhaled essential oils have potential benefit for pain in labor or childbirth (moderate confidence) and for blood pressure reduction in patients with hypertension (low confidence). Two systematic reviews provided low-confidence evidence of potential positive effects on sleep quality in various populations. There is moderate-confidence evidence that aromatherapy has no effect on anxiety in palliative care. The effects of inhaled essential oils are unclear for nausea/vomiting in all studied populations, and for all other conditions studied. Among the topical essential oil interventions, there is evidence of potential effectiveness in the use of tea tree oil for tinea pedis and the level of confidence in the evidence is moderate. The effectiveness of topical essential oils is unclear for fungal infection of the nails (onychomycosis), acne, and episiotomy wound healing.

Anxiety and depression

A major review published in 2000 ⁵¹ focused on six studies investigating treatment or prevention of anxiety with aromatherapy massage. Although the studies suggested that aromatherapy massage had a mild transient anxiolytic effect, the authors concluded that the research done at that time was not sufficiently rigorous or consistent to prove the effectiveness of aromatherapy in treating anxiety. This review excluded trials related to other effects of aromatherapy (such as pain control) and did not include any studies looking at the effects of odors that were not specifically labeled as aromatherapy ⁵¹.

Another randomized controlled trial investigated the effects of massage or aromatherapy massage in 103 cancer patients who were randomly assigned to receive massage using a carrier oil (massage group) or massage using a carrier oil plus the Roman chamomile essential oil (Chamaemelum nobile [L.] All. [synonym: Anthemis nobilis L.]) (aromatherapy massage group) ⁵². Two weeks after the massage, a statistically significant reduction was found in anxiety in the aromatherapy massage group (as measured by the State-Trait Anxiety Inventory) and improvement in symptoms (as measured by the Rotterdam Symptom Checklist [RSCL]). The subscales with improved scores were psychological, quality of life (QOL), severe physical, and severe psychological. The massage-only group showed improvement on four RSCL subscales; however, these improvements did not reach statistical significance ⁵².

A study that evaluated an aromatherapy service following changes made after an initial pilot at a U.K. cancer center, also reported on the experiences of patients referred to the service ⁵³. Of the 89 patients originally referred, 58 patients completed six aromatherapy sessions. Significant improvements in anxiety and depression (as measured by the Hospital Anxiety and Depression Scale [HADS]) were reported at the completion compared with before the six sessions ⁵³.

A placebo-controlled, double-blind, randomized trial conducted in Australia investigated the effects of inhalation aromatherapy on anxiety during radiation therapy ⁵⁴. A total of 313 patients who received radiation therapy were randomly assigned to one of three groups (carrier oil with fractionated essential oils, carrier oil only, or pure essential oils of lavender, bergamot (Citrus aurantium L. ssp. bergamia [Risso] Wright & Arn. [Rutaceae]; [synonym: Citrus bergamia Risso]), and cedarwood (Cedrus atlantica [Endl.] Manetti ex Carriere [Pinaceae])). All three groups received the oils by inhalation during radiation therapy. There were no significant differences reported in depression (as measured by HADS) or psychological effects (as measured by the Somatic and Psychological Health Report) between the groups ⁵⁴. The group that received carrier oil only showed a statistically significant decrease in anxiety (as measured by HADS) compared with the other two groups ⁵⁴.

Sleep

A placebo-controlled, double-blind, crossover, randomized trial compared an essential oil (choice of lavender, peppermint, or chamomile) with a pleasant-smelling placebo (rose water) administered by diffuser overnight for 3 weeks in 50 adult patients with newly diagnosed acute myeloid leukemia who were hospitalized for administration of intensive chemotherapy ⁵⁵. Most patients reported poor quality sleep on the Pittsburgh Sleep Quality Index (PSQI) at baseline, with a mean score of 12.7 ⁵⁵. During the aromatherapy week, the mean PSQI score decreased to 9.7, but returned to a near-baseline score of 12.4 during the washout week. The difference in mean PSQI score and mean placebo score was statistically significant ⁵⁵. Aromatherapy also reduced the weekly average Edmonton Symptom Assessment Scale–Revised (ESASr) score by 6.06 points, which was statistically significant ⁵⁵. All subscales demonstrated a reduction in ESASr score with six symptom score changes showing a statistically significant benefit from aromatherapy:

• Tiredness
• Drowsiness
• Lack of appetite
• Depression
• Anxiety
• Well-being

Another randomized controlled trial examined the effects of aromatherapy massage and massage alone in 42 patients with advanced cancer over a 4-week period ⁵⁶. Patients were randomly assigned to receive weekly massages with or without aromatherapy; the treatment group (aromatherapy group) received massages with lavender essential oil (Lavandula angustifolia Miller [synonyms: Lavandula spicata L.; Lavandula vera DC.]) and an inert carrier oil, and the control group (massage group) received either an inert carrier oil alone or no intervention. No significant long-term benefits of aromatherapy or massage in pain control, QOL, or anxiety were reported, but sleep scores (as measured by the Verran and Snyder-Halpern sleep scale) improved significantly in both groups ⁵⁶. A statistically significant reduction in depression scores was also reported (as measured by the Hospital Anxiety and Depression Scale [HADS]) in the massage-only group ⁵⁶.

A randomized controlled trial of lavender, tea tree oil, or no-treatment control in adult patients who received outpatient chemotherapy with paclitaxel reported that trait anxiety and sleep quality improved with lavender, and that tea tree oil led to the highest change in sleep quality ⁵⁰. However, changes in anxiety were observed only on the trait anxiety scores, not on the state anxiety scores, which may reflect short term changes associated with an aromatherapy intervention. In addition, there were no significant differences in sleep scores between the two aromatherapy groups and the controls, which the study was designed to detect ⁵⁰.

Dry mouth

Radioactive iodine damage to normal salivary glands may be minimized by increased saliva production during the period of treatment. Inhalation aromatherapy was evaluated for its ability to increase saliva production during this administration period ⁵⁷. An aromatherapy intervention consisting of a 2:1 mixture of lemon and ginger essential oils versus a distilled water (no smell) control inhaled for 10 min/d during a 2-week hospitalization for administration of radioactive iodine therapy for differentiated thyroid cancer was investigated in a randomized controlled trial of 71 patients. Salivary gland function was assessed by scintigraphy ⁵⁷. Compared with placebo, those in the aromatherapy group showed a significantly higher rate of change of the maximum accumulation ratio in the parotid and submandibular glands and a significantly increased rate of change of the washout ratio before and after therapy in the bilateral parotid glands ⁵⁷. Although an increasing trend was observed for the submandibular glands in subjects receiving aromatherapy, no significant differences were noted between the groups ⁵⁷. These results suggest that by increasing saliva production during radioactive iodine treatment with inhalation aromatherapy with a lemon and ginger combination, increased iodine clearance in salivary glands may lead to reductions in long-term damage to saliva production ⁵⁷.

Nausea and vomiting

A randomized, controlled, crossover trial investigated the effects of inhaled ginger essential oil on alleviating chemotherapy-induced nausea and vomiting in Asian women with breast cancer ⁵⁸. Aromatherapy administered as inhaled ginger essential oil for 5 days was associated with small statistically significant, but not clinically significant, reductions in acute nausea and had limited effects on reducing vomiting or delaying nausea in 60 evaluable patients ⁵⁸.

In a placebo-controlled, double-blind, randomized trial of bergamot inhalation aromatherapy compared with a pleasant-smelling shampoo that did not contain essential oils administered at the time of stem cell infusion in 37 children and adolescents undergoing stem cell transplant, aromatherapy was not found to be beneficial in reducing nausea, anxiety, or pain ⁵⁹. As administered in this study, bergamot inhalation aromatherapy may have contributed to persistent anxiety after the infusion of stem cells. Although no more effective than placebo, parents receiving aromatherapy showed a significant decrease in their transitory anxiety during the period between the completion of their child’s infusion and 1 hour after infusion ⁵⁹. Nausea and pain subsided over the course of the intervention for all children, although nausea remained significantly greater in patients who received aromatherapy. These findings suggest that the diffusion of bergamot essential oil may not provide suitable anxiolytic and antiemetic effects among children and adolescents undergoing stem cell transplantation ⁵⁹. The double-blinding of the trial may explain the results, as single-blinded or nonblinded trials in general supported the aromatherapy intervention.

A similar study evaluated the efficacy of an aromatherapy intervention for reduction of symptom intensity of nausea, retching, and/or coughing among adult patients who received stem cells preserved in dimethyl sulfoxide ⁶⁰. The study found that an intervention of tasting or sniffing sliced oranges was more effective at reducing symptom intensity compared with orange essential oil inhalation aromatherapy ⁶⁰.

Procedure-related symptoms

In a randomized placebo-controlled study of two different types of external aromatherapy tabs (lavender-sandalwood and orange-peppermint) compared with a matched placebo-controlled delivery system in 87 women undergoing breast biopsies, there was a statistically significant reduction in self-reported anxiety with the use of the lavender-sandalwood aromatherapy tab compared with the placebo group ⁶¹.

In a three-arm randomized trial of 123 patients that compared lavender, eucalyptus, and no essential oil administered via inhalation, procedural pain after needle insertion into an implantable central venous port catheter was significantly decreased in the lavender oil inhalation aromatherapy group compared with the control group ⁶². Inhalation of eucalyptus oil did not reduce procedural pain levels during needle insertion ⁶².

Health-related Quality of Life

A randomized, controlled, pilot study examined the effects of adjunctive aromatherapy massage on mood, Quality of Life (QOL), and physical symptoms in patients with cancer ⁶³. Forty-six patients were randomly assigned to either conventional day care alone or day care plus weekly aromatherapy massage using a standardized blend of essential oils (1% lavender and chamomile in sweet almond carrier oil) for 4 weeks ⁶³. Patients self-rated their mood, QOL, and the intensity of the two symptoms that were the most concerning to them at the beginning of the study and at weekly intervals thereafter. Of the 46 patients, only 11 of 23 patients (48%) in the aromatherapy group and 18 of 23 patients (78%) in the control group completed all 4 weeks. Patient-reported mood, symptoms, and QOL improved in both groups, and there were no statistically significant differences between the two groups in any of these measures ⁶³.

Aromatherapy mechanism of action

Theories about the mechanism of action of aromatherapy with essential oils differ, depending on the community studying them. Proponents of aromatherapy often cite the connection between olfaction and the limbic system in the brain as the basis for the effects of aromatherapy on mood and emotions; less is said about proposed mechanisms for its effects on other parts of the body. Most of the aromatherapy literature, however, lacks in-depth neurophysiological studies on the nature of olfaction and its link to the limbic system, and it generally does not cite research that shows these links. Proponents of aromatherapy also believe that the effects of the treatments are based on the special nature of the essential oils used and that essential oils produce effects on the body that are greater than the sum of the individual chemical components of the scents.

These assertions have been contested by the biochemistry and psychology communities, which take a different view of the possible mechanism of action of odors on the human brain (most do not differentiate the odors produced by essential oils from those of synthetic fragrances) ²⁷. This neurobiological view, which focuses mostly on the emotional and psychological effects of fragrances (as opposed to the other symptomatic effects claimed by aromatherapists), takes into account what is known about olfactory transduction and the connection of the olfactory system to other central nervous system functions, including memory; however, it is primarily theoretical because of the lack of significant research addressing this topic.

Numerous studies on the topical antibacterial effects of essential oils have been published; most have found the essential oils to have significant antimicrobial activity ⁶⁴. Some essential oils are antiviral and inhibit replication of the herpes simplex virus ⁶⁵. Other essential oils are fungistatic and fungicidal against both vaginal and oropharyngeal Candida albicans ⁶⁶.

Studies on rats in Europe and Japan have shown that exposure to various odors can result in stimulation or sedation, as well as changes in behavioral responses to stress and pain. A study ⁶⁷ on the sedative effects of essential oils and other fragrance compounds (mostly individual chemical components of the essential oils) on rat motility showed that lavender oil (Lavandula angustifolia Miller [synonyms: Lavandula spicata L.; Lavandula vera DC.]) in particular had a significant sedative effect, and several single-oil constituents (as opposed to whole essential oils) had similarly strong effects. The authors do not comment on the presumed mechanism for this effect ⁶⁷. The differences in bioavailability are ascribed to different levels of lipophilicity, with the more lipophilic oils producing the most sedative effects. The researchers also found significant plasma levels of the fragrance compounds after inhalation, suggesting that the effects of aromatherapy result from a direct pharmacological interaction rather than an indirect central nervous system relay ⁶⁷.

Other studies have investigated the effects of aromatherapy on rats’ behavioral and immunological responses to painful, stressful, or startling stimuli. In two European studies, rats exposed to pleasant odors during painful stimuli exhibited decreased pain-related behaviors, with some variation in response between the sexes ⁶⁸, ⁶⁹. Two studies from Japan showed an improvement in immunological and behavioral markers in rats exposed to fragrances while under stressful conditions ⁷⁰, ⁷¹.

Aromatherapy uses

Aromatherapy is used or claimed to be useful for a vast array of symptoms and conditions. Aromatherapy is used with other complementary treatments (e.g., massage and acupuncture) as well as with standard treatments for symptom management. Essential oils are available in the United States for inhalation and topical treatment. Topical treatments are generally used in diluted forms. Aromatherapy is not widely administered via ingestion. Published studies regarding the uses of aromatherapy have generally focused on its psychological effects (used as a stress reliever or anxiolytic agent) or its use as a topical treatment for skin-related conditions.

A large body of literature has been published on the effects of odors on the human brain and emotions. Some studies have tested the effects of essential oils on mood, alertness, and mental stress in healthy participants. Other studies investigated the effects of various (usually synthetic) odors on task performance, reaction time, and autonomic parameters or evaluated the direct effects of odors on the brain via electroencephalogram patterns and functional imaging studies ⁶⁷. Such studies have consistently shown that odors can produce specific effects on human neuropsychological and autonomic function and that odors can influence mood, perceived health, and arousal. These studies suggest that odors may have therapeutic applications in the context of stressful and adverse psychological conditions.

Practitioners of aromatherapy apply essential oils using several different methods, including the following:

1. Indirect inhalation: The patient breathes in an essential oil by using a room diffuser, scented room spray or heated candle wax, which spreads the essential oil through the air, or by placing drops on a tissue or piece of cotton nearby.
2. Direct inhalation: The patient breathes in an essential oil by using an individual inhaler made by floating essential oil drops on top of hot water.
3. Topical application with skin absorption of the essential oil. Examples include massage, scented bath, cosmetics, and perfumes. In aromatherapy massage, one or more essential oils is diluted into a carrier oil and massaged into the skin.
4. Oral absorption of the essential oil. Examples include gelatin capsules and safe dose of essential oil diluted.
5. Internal absorption of essential oil. Examples include scented mouthwash and scented suppository or vagina douche. Essential oil used for flavor in prescription medications and herbal medicines ⁴⁴.

Essential oils may also be mixed with bath salts and lotions or applied to bandages.

Different aromatherapy practitioners may have different recipes for treating specific conditions, involving various combinations of essential oils and methods of application. Differences seem to be practitioner dependent, with some common uses more accepted throughout the aromatherapy community. Training and certification in aromatherapy for lay practitioners is available at several schools throughout the United States and United Kingdom; however, there is no professional standardization in the United States and no license is required to practice in either country. Thus, there is little consistency among practitioners in the specific treatments used for specific illnesses. This lack of standardization has led to variability in therapeutic protocols used in research on the effects of aromatherapy. Anecdotal evidence alone or previous experience has driven the choice of essential oils and different researchers choose different essential oils when studying the same applications. However, now there are specific courses for licensed health professionals that give nursing or continuing medical education credit hours, including a small research component and information about evaluating and measuring outcomes.

Aromatherapy oils side effects

Safety testing on essential oils has shown minimal adverse effects. Several essential oils have been approved for use as food additives and are classified as GRAS (generally recognized as safe) by the U.S. Food and Drug Administration; however, ingestion of large amounts of essential oils is not recommended. Sometimes people think that if an “essential oil” or other ingredient comes from a plant, it must be safe. But many plants contain materials that are toxic, irritating, or likely to cause allergic reactions when applied to the skin. Some essential oils (e.g., camphor oil) can cause local irritation; therefore, care should be taken when applying them. A few cases of contact dermatitis have been reported, mostly in aromatherapists who have had prolonged skin contact with essential oils in the context of aromatherapy massage ⁷². Essential oils can be dangerous and toxic, with some being flammable, causing skin dermatitis, being phototoxic with risk of a chemical burn, or causing oral toxicity or death. Phototoxicity has occurred when essential oils (particularly citrus oils) are applied directly to the skin before sun exposure. Cumin oil is safe in food, but can cause the skin to blister. Certain citrus oils used safely in food can also be harmful in cosmetics, particularly when applied to skin exposed to the sun. One case report also showed airborne contact dermatitis in the context of inhaled aromatherapy without massage ⁷³.

Often, aromatherapy uses undefined mixtures of essential oils without specifying the plant sources. Allergic reactions are sometimes reported, especially after topical administration. As essential oils age, they are often oxidized so the chemical composition changes. Individual psychological associations with odors may result in adverse responses. Repeated exposure to lavender and tea tree oils by topical administration was shown in one study to be associated with reversible prepubertal gynecomastia ⁷⁴. The effects appear to have been caused by the purported weak estrogenic and antiandrogenic activities of lavender and tea tree oils. Therefore, avoiding these two essential oils is recommended in patients with estrogen-dependant tumors ⁷⁴. However, this is the first published report of this type of adverse effect when using products containing tea tree or lavender oils ⁷⁴.

Fire safety

TF is a 54-year-old man who lives in Phoenix, Arizona; he is an advocate of essential oils and frequently uses them for anxiety and to promote sleep. On his day off, TF has several errands, including his monthly supply of essential oils. His first errand was to purchase essential oils. During his last errand, TF heard his name being called by an old friend. TF sat down to visit with his friend for a few minutes; the visit lasted 45 minutes. When TF returned to his car, he found black smoke in the car and a large burnt hole in his backseat where his purchased essential oils were placed. TF called the police to file a report.

Critical analysis revealed the large supply of essential oils were stored in the back seat. TF left the oils in the car for 45 minutes with the outside temperature of 112°F (44.4 °C), with the potential increase in the temperature in the car increasing to 160°F (71.1 °C). The essential oils caught on fire, resulting in the smoke and burnt hole in the backseat of the car.

Intervention for this unsafe use of essential oil is education that these oils are flammable and need to be stored in a cool dark place in the original bottle, which is colored to prevent direct sunlight penetrating to the essential oil. Unsafe storage by leaving essential oils in a hot car can cause a combustion reaction, triggering flames and a fire.

Elder and Child Safety

CF, a 66-year-old woman, was admitted for inpatient treatment of sepsis from an acute urinary infection. At night she can become agitated and screamed that snakes were crawling up her wall. The provider ordered aromatherapy and increased lighting in the room. Turning on a bed alarm and increased rounding also were ordered. The nurse brought the aromatherapy essential oil to the room and left to get a steam diffuser. When the nurse returned, CF appeared drunk. The nurse found the bottle open on the bedside table. The nurse called for assistance.

Critical analysis revealed the nurse left the bottle of essential oil on the nightstand unattended when she left the room. The patient was able to open the bottle and drink a small amount of the essential oil, causing the drunken behavior.

Intervention for essential oil left attended with a confused elderly patient was administration of milk to dilute the essential oil. The provider was called for further orders and an incident report was completed. The elderly and children are vulnerable to adverse effects from inappropriate use of essential oils. Early recognition is appearing drunk. Essential oils should be locked in a container in a hospital and kept away from elders and children. An essential oil bottle should not be left unattended, especially with this confused patient with delusions. The diffuser with the essential oil needs to be prepared outside of the patient’s room.

Allergic Contact Dermatitis and Primary Contact Dermatitis

TA, a 30-year-old woman, works at a massage therapist and is extremely popular. Bookings must be in advance because her schedule stays full. Each day she works 8 hours to 9 hours, with mostly 1.5-hour massages. She uses a lotion with an aromatic essential oil. After 3 months, she developed a bright bred rash on her hands and lower arms. She used a steroid cream on the rash without resolving the rash. Over the next month, the rash got worse. TA scheduled an appointment with a dermatologist.

Critical analysis evaluated allergic contact dermatitis versus primary contact dermatitis. In allergic contact dermatitis, the allergy occurs over a period whereas primary contact dermatitis occurs the first time the essential oil is used. In allergic contact dermatitis, the symptoms are a bright red rash that worsens with time whereas the primary contact dermatitis a presents as a red wheal or burn ⁷⁵.

Intervention was based on treating allergic contact dermatitis based on symptomatology and length of time. Patch testing revealed the specific essential oil to stop using, allowing her to continue as a massage therapist. If TA had primary contact dermatitis, the red wheal or burn area from the toxic oil would be diluted with vegetable oil or milk then washed with unscented soap ⁷⁵.

Essential Oil Phototoxicity

AJ is a 34-year-old woman who loves the sun. She lives in an apartment with a swimming pool. The average summer temperature is 102°F. On weekends she can be found at the swimming pool for 4 hours per weekend day. AJ’s pool relaxing is 4 hours to 5 hours per day. She sets an alarm hourly to turn from back to stomach. AJ says the sunrays lift her up and gives her a beautiful brown tan with sunscreen oil. Due to the shutdown of her state due to COVID-19 and stores closed, AJ decided to shop online for home delivery of essential oils. AJ found a Web site with a sale on essential oils that had a pop-up advertisement declaring breaking news that essential oils prevent and cure the COVID-19 virus. AJ purchased several citrus fruit essential oils. AJ applied a mandarin essential oil to her neck and chest to ward off the COVID-19 virus. AJ left the pool early because of a burning sensation on her neck and chest. She took a shower and noticed several burned areas. The next day, the red burned areas turned to a brown skin damage appearance unlike any sunburn she ever experienced. AJ scheduled a dermatologist appointment due to the discoloration and discomfort not resolving ¹³.

Critical analysis revealed that AJ was scammed by a fraudulent online statement to sell essential oils in a pandemic COVID-19 fearful time. The mandarin essential oil was not diluted when applied to the skin, increasing the risk for dermal toxicity. The pure mandarin essential oil was phototoxic and inflected damage to the skin, resulting in dark pigmented skin that could be permanent ¹³. Dermal toxicity also occurred with the essential oil not being diluted. The regular sunburn resulted in redness and blisters on her skin. AJ scheduled an urgent dermatology appointment. She used an over-the-counter steroid cream for pain relief.

The intervention to stop using the phototoxic essential oil and seek a specialist, which AJ did, with scheduling the dermatology appointment. The essential oil label always should be read for safety instructions. If a photosensitivity essential oil is used, wait a minimum of 12 hours before exposure to sun ultraviolet radiation. AJ should consult a qualified aromatherapist who has training for aromatherapy, not a seller of essential oils, to prevent harm from essential oils. A registry database for trained aromatherapists who have passed the core level of aromatherapy examination can be found at thttps://www.aromatherapycouncil.org.uk/about_us 10 Essential oils always should be diluted in a carrier oil. A carrier oil prevents irritation to the skin and side effects of the essential oil. Examples of carrier oils include coconut oil, coconut oil, aloe vera gel, unscented lotion, vegetable oil, and avocado oil. Because oil and water do not mix, milk is used to remove the oil and calm the skin followed by washing of the skin by unscented soap ⁷⁵.

Phototoxic essential oil contains constituents that triggers a chemical process that changes the skin DNA, making the skin susceptible to sun ultraviolet radiation. This chemical change in the skin is called photosensitivity and the primary constituent is confurocoumarins that causes phototoxic reaction. Exposure of the applied photosensitivity essential oil to ultraviolet radiation from the sun inflicts skin damage with darkly pigmented skin that can be permanent due to the long period of exposure to sun ultraviolet radiation ⁷⁵. It is extremely important to determine if an essential oil is phototoxic. AJ should find this warning on the label of the essential oil. Essential oils are not regulated by the FDA but the FDA monitors Web sites for fraudulent postings.

Oral Toxicity

LM, a 110-pounds 20-year-old woman who lived with her mother, was told by an essential oil seller that she heard essential oils could prevent and cure COVID-19. LM was terrified that she could contract the virus with a resurgence of COVID-19 later in the year. LM was extremely excited about this information and asked which essential oil she should use orally to protect herself from this deadly pandemic COVID-19 virus. The seller recommended a safe dose for eucalyptus essential oil twice weekly orally. After a week LM decided to increase the oral dose to ward off the COVID-19 virus. She decided to drink half of an 8 oz glass of eucalyptus essential oil. Within 10 minutes she experienced burning in her throat, mouth, and stomach ⁷⁵. LM yelled for her mother to come quickly. The mother found the daughter vomiting, staggering, and with slurred speech. The mother found the eucalyptus essential oil bottle and a glass indicating she had drunk eucalyptus essential oil. The mother called 911 with the dispatcher sending an ambulance and notifying the Poison Control Center for eucalyptus poisoning.

Critical analysis of oral toxicity of eucalyptus revealed LM had drunk an unsafe dose causing poisoning with central nervous system depression and a chemical burn in her mouth, throat, and stomach. LM was admitted to the intensive care unit.

Intervention was police investigation of the fraudulent information that eucalyptus could prevent and cure COVID-19 information by the seller of the essential oil with unintentional poisoning LM. A qualified aromatherapist that is certified or completed aromatherapy curriculum. Don’t take advise from a seller of essential oils without expertise. Seek consultation for safe use of essential oils. Even with a safe oral dose of eucalyptus can cause harm. Safe use of essential oils is to not take essential oils internally. It is extremely important that induced vomiting is not done for this toxicity.

Oral toxicity symptoms are rapid decline with complaint of burning in the mouth and throat and abdominal pain. Central nervous symptoms are ataxia and respiratory depression, and, with a higher dose, possible nasal intubation is needed for mechanical ventilation and deep coma. Death can occur with a toxic dose ⁷⁵.

Eye Safety

MF accidently splashed essential oil in an eye when she was preparing essential oil for a diffuser. Her eye was burning and painful and her vision blurred in the eye.

Critical analysis reveals essential oils are toxic to eyes and can result in a chemical burn. The eye should be rapidly irrigated with milk or a vegetable oil carrier. A washcloth or cotton ball can help with the irrigation. After treatment flush the eye with water. Do not flush the eye with water initially due to oil and water not mixing.

Aromatherapy summary

Aromatic scents and oils used in clinical aromatherapy can be beneficial for symptom management such as pain, nausea, vomiting, anxiety, depression, stress, insomnia, agitation with dementia, cancer pain, and end of life symptoms, Clinical aromatherapy has been found beneficial in the inpatient and outpatient settings especially critical care, oncology, palliative care, hospice, and surgical. On the flip side, aromatic essential oils can be dangerous and toxic due to certain oils being flammable, causing skin dermatitis, or being phototoxic, with risks of chemical burn, oral toxicity, and even death.

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