Essential Oils at a Glance: Evidence and Safety Table
A side-by-side table of 37 essential oil pages with the plant's checked scientific name, the evidence label from each oil's page, and the main safety point sources describe. Not a ranking.
Content last updated . This page has not been medically reviewed.
Safety first. Natural products can cause side effects and interact with medicines. Read essential oil safety before you use anything on this page.
Safety first. Essential oils are not for swallowing, and the oils in this table range from mild to dangerous if swallowed. If anyone may have swallowed one, call Poison Help at 1-800-222-1222 (US); call 911 for collapse, a seizure or trouble breathing. [1] See the safety quick reference.
This table puts the oils covered in this library side by side so you can see, at a glance, which plant each oil comes from, what the evidence in people looks like, and the main safety point that sources raise. It is not a ranking, not a "best oils" list and not a guide to what to use. Oils are in alphabetical order within each group. A row is a summary; the linked page holds the studies and the full safety picture.
How to read the table
- Plant. The scientific name is checked against GBIF, the global plant-name database, on 2026-10-23. [2] Where GBIF treats a name used on labels and in papers as a synonym, the row says so. Which plant part and which species a product uses can differ between products, so check the label (reading a label).
- Evidence in people. This is the label given on each oil's own page, where the studies behind it are named. This table adds no new studies. Labels mean what they mean on the rest of the site: see evidence labels. Most aromatherapy trials are small and short, are hard to blind because people can smell what they are given, and often measure self-reported feelings, so even "promising but limited" is modest. Dish and animal studies are not counted here.
- Main safety point. One point that a source we read raises for that oil. "General" means we did not read an oil-specific warning for this table. That is not proof of safety. Poison Control says many essential oils can cause rashes on skin and some can be poisonous if absorbed through the skin or swallowed. [1]
Most searched oils
| Oil | Plant | Evidence in people (label on its page) | Main safety point |
|---|---|---|---|
| Eucalyptus oil | Eucalyptus globulus; the EMA also names E. polybractea and E. smithii [3] | Traditional use only for cough with a cold (the EMA found trial evidence insufficient but the effect plausible); insufficient evidence for asthma and bronchitis [3] | Swallowed, it can cause seizures. [1] EU medicines are not for children under 30 months or with a history of seizures. [3] |
| Frankincense oil | Boswellia sacra and other Boswellia species | Promising but limited, mostly from blends | General |
| Lavender oil | Lavandula angustifolia | Promising but limited (an oral capsule product for anxiety); mixed (inhaled, for anxiety and sleep) | Allergic skin reactions are possible; aromatherapy with it may cause headache or coughing; NCCIH sees theoretical reasons it might interact with some sedative drugs or herbs, which matters before surgery. [4] |
| Peppermint oil | Mentha × piperita | Promising but limited (capsules for IBS, skin use for tension headache, inhaled for nausea); no good evidence of benefit for indigestion alone [5] | Not for the face of infants or young children, because of menthol. [5] The EMA says its peppermint oil medicines must not be used under age 2. [6] |
| Rosemary oil | Salvia rosmarinus (older name Rosmarinus officinalis) | Promising but limited (small trials for hair loss, memory and mood) | General |
| Tea tree oil | Melaleuca alternifolia | Promising but limited (acne, athlete's foot); insufficient for other uses [7] | Swallowing can cause confusion, unsteadiness and coma. [7] Even a few concentrated drops can poison pets. [8] Oxidized oil is more allergenic. [9] |
Citrus oils
Several citrus oils can make skin react to sunlight. The FDA notes that certain citrus oils used safely in food can be harmful in cosmetics, particularly on skin exposed to the sun. [10] An aromatherapy association lists expressed (pressed) lemon, lime and bitter orange as photosensitizers and lists distilled lemon and distilled lime as non-phototoxic. [11] See citrus oils and sunlight.
| Oil | Plant | Evidence in people (label on its page) | Main safety point |
|---|---|---|---|
| Bergamot oil | Named Citrus bergamia on papers; GBIF treats it as a synonym of Citrus × limon [2] | Promising but limited (small trials on stress and PMS symptoms) | Blistering sun reactions are documented. [12] The aromatherapy association lists it as a photosensitizer, and a bergapten-free type as non-phototoxic. [11] |
| Grapefruit oil | Citrus × paradisi; GBIF treats it as a synonym of Citrus × aurantium [2] | Promising but limited (PMS symptoms, procedure discomfort) | The aromatherapy association lists it as a photosensitizer of low risk. [11] |
| Lemon oil | Citrus × limon | Promising but limited (small trials on mood and nausea) | Pressed lemon oil is listed as a photosensitizer; distilled as non-phototoxic. [11] |
| Lime oil | Citrus × aurantiifolia | Proper evidence not found | Pressed lime oil is listed as a photosensitizer; distilled as non-phototoxic. [11] |
| Mandarin and tangerine oil | Citrus reticulata | No good evidence of benefit in the one infant trial; insufficient evidence otherwise | The aromatherapy association lists mandarin-tangerine among non-phototoxic citrus oils. [11] |
| Orange oil (sweet and bitter) | Citrus sinensis (GBIF: synonym of Citrus × aurantium) and bitter orange, Citrus × aurantium [2] | Insufficient evidence for general use; promising but limited in single small trials (labor, chemotherapy nausea) | Pressed bitter orange oil is listed as a photosensitizer; sweet orange as non-phototoxic. [11] |
Floral and herbal oils
| Oil | Plant | Evidence in people (label on its page) | Main safety point |
|---|---|---|---|
| Basil and marjoram oils | Ocimum basilicum; Origanum majorana [2] | Insufficient evidence; one trial of basil oil on skin in migraine was promising but limited | General |
| Chamomile oil | Roman, Chamaemelum nobile; German, Matricaria chamomilla [2] | Promising but limited (small inhaled trials) | Daisy-family allergy: people allergic to ragweed, chrysanthemums, marigolds or daisies are more likely to react to chamomile (NCCIH, about the herb). [13] |
| Clary sage oil | Salvia sclarea | Insufficient evidence; blood pressure results are lab markers | Poison Control reports seizures in children after swallowing more than a very small amount of sage (Salvia) oil; it does not say which sage. [1] |
| Geranium oil | Pelargonium graveolens | Promising but limited (small inhaled trials on anxiety) | Skin allergen: geranium oil bourbon was among substances reacting at 2% or more in 178 fragrance-sensitive patients. [14] |
| Helichrysum oil | Helichrysum italicum | Mostly preclinical; proper evidence not found for scars | General |
| Jasmine and rose oils | Jasminum grandiflorum; Rosa × damascena [2] | Promising but limited (rose, for pain and sleep) | Jasmine absolute caused 1.8% positive patch tests in one clinic network. [15] |
| Lemongrass oil | Cymbopogon flexuosus, C. citratus and others; studies vary [2] | Promising but limited (small trials); mixed (mosquito repellency) | 2.6% positive patch tests in one clinic network. [15] An EFSA opinion says to treat the oil as an irritant and a sensitiser. [16] |
| Neroli oil | Citrus × aurantium (blossom) | Promising but limited (small inhaled trials) | 1.1% positive patch tests in one clinic network. [15] |
| Spearmint oil | Mentha spicata | Promising but limited (one small trial for chemotherapy nausea) | Spearmint oil reacted at 2% or more in fragrance-sensitive patients. [14] |
| Vetiver oil | Chrysopogon zizanioides | Promising but limited (small trials); mixed to no good evidence as a mosquito repellent | General |
| Ylang ylang oil | Cananga odorata | Mixed | The most positive patch tests (3.9%) of 12 oils in one clinic network. [15] |
Woody, resin and earthy oils
| Oil | Plant | Evidence in people (label on its page) | Main safety point |
|---|---|---|---|
| Cedarwood oil | Several unrelated trees, for example Juniperus virginiana and Cedrus atlantica [2] | Promising but limited (a four-oil blend for patchy hair loss); otherwise insufficient | An EFSA opinion on one cedarwood oil (Juniperus deppeana) says it is an irritant to skin and eyes and a skin and respiratory sensitiser. [17] |
| Cypress oil | Cupressus sempervirens | Proper evidence not found | General |
| Juniper berry oil | Juniperus communis | Traditional use only (EU); no clinical trials of the oil | The EU monograph does not recommend the oil medicine in pregnancy or breastfeeding and lists severe kidney disease among its contraindications. [18] |
| Myrrh oil | Commiphora myrrha [2]; the EMA writes C. molmol [19] | Traditional use only (EU, for a resin tincture, not the oil); promising but limited in two massage trials of blends | The EMA's conclusions cover an alcohol extract of the resin, not the essential oil. [19] |
| Patchouli oil | Pogostemon cablin | Promising but limited (one small trial); the rest is preclinical | An EFSA opinion says to treat it as an irritant to skin and eyes and a respiratory sensitiser. [20] |
| Pine oil | Pinus sylvestris, P. pinaster and others | Proper evidence not found | Case reports of swallowed pine-oil cleaners describe central nervous system depression, breathing failure and lung inflammation. [21][22] |
| Sandalwood oil | Santalum album | Insufficient evidence | 1.8% positive patch tests in one clinic network. [15] |
Spice and strong oils
| Oil | Plant | Evidence in people (label on its page) | Main safety point |
|---|---|---|---|
| Camphor oil | Cinnamomum camphora | Not assessed for benefit; the page covers dangers | Even a small amount is dangerous if swallowed and seizures can start within minutes. [1] A cluster of toddlers had seizures after swallowing camphor or repeated skin rubbing. [23] |
| Cinnamon oil | Cinnamomum verum; C. aromaticum [2] | Insufficient evidence; one small trial found no benefit for nausea | Topical cinnamon oil or powder may cause skin irritation or contact dermatitis. [24] |
| Clove oil | Syzygium aromaticum | Promising but limited (dental pain) | A 15-month-old developed fulminant liver failure after swallowing 10 ml. [25] 1.6% positive patch tests in one clinic network. [15] |
| Oregano oil | Origanum vulgare | Promising but limited (one small study); a marketing claim for infections | Listed by the aromatherapy association as a dermal irritant. [11] |
| Pennyroyal oil | Mentha pulegium [2] | Traditional use only; evidence of harm | Taken by mouth it is highly toxic to the liver and has been linked to deaths. [26] |
| Thyme oil | Thymus vulgaris | Promising but limited (one inhalation trial) | Listed by the aromatherapy association as a dermal irritant. [11] |
| Wintergreen oil | Gaultheria procumbens | Proper evidence not found | Very dangerous if more than a tiny amount is swallowed. [1] A review links a teaspoon or less to deaths in children under 6. [27] A review says excessive use of topical methyl salicylate products in people taking warfarin may cause bleeding. [28] |
What the table cannot tell you
- It is not a safety clearance. An empty or "General" cell means no oil-specific warning was read for this table, not that the oil is safe.
- Nothing here transfers between forms. A result for an oil in a capsule, a massage blend, a room scent or a lab dish does not carry over to a bottle of oil. Poison Control says it can be hard to know exactly what is in a bottle. [1]
- Patch-test percentages are clinic figures. The clinic-network numbers come from people with skin problems, so they are not rates for the general public. [15]
- Oils not listed. Oils without a profile page in this library are not in the table. Their absence is not a judgment.
- Medicines. Poison Control says essential oils may interact with medications. [1] Ask a pharmacist; see medication interactions.
For word meanings see the glossary; for common questions see the FAQ.
Frequently asked questions
Is this a list of the best essential oils?
No. It is alphabetical within groups and does not rank oils. The sources we read did not compare oils head to head. The FDA notes that an ingredient is not necessarily safe because it comes from a plant. [10]
Which oil has the strongest evidence?
No row carries the label "established". The best-supported entries are limited trials, such as peppermint oil capsules for IBS, which a 2022 review of 10 studies found better than placebo for symptoms but with more side effects. [5]
Why are some plant names different from the labels?
Plant databases revise names. GBIF, for example, lists Citrus bergamia and Citrus × paradisi as synonyms of other names, so you may see either on labels and papers. [2]
Why do some rows give percentages from clinics?
They show how often skin allergy appeared in dermatology clinic patients tested for it. One network found 8.3% of those tested reacted to at least one of 12 oils. [15]
Where do I check an oil that is not in the table?
Start with the safety quick reference and ask a pharmacist. NCCIH advises talking with your health care providers about any complementary health approach you use. [5]
References
- Poison Control (National Capital Poison Center). Essential oils: Poisonous when misused. Read 2026-10-23.
- GBIF Secretariat. GBIF Backbone Taxonomy: species name matching for the 47 plant names in the oil table and glossary. Queried 2026-10-23. Read 2026-10-23.
- European Medicines Agency (EMA). Eucalypti aetheroleum - herbal medicinal product. Read 2026-10-23.
- National Center for Complementary and Integrative Health (NCCIH). Lavender. Read 2026-10-23.
- National Center for Complementary and Integrative Health (NCCIH). Peppermint Oil. Read 2026-10-23.
- European Medicines Agency (EMA). Menthae piperitae aetheroleum - herbal medicinal product. Read 2026-10-23.
- National Center for Complementary and Integrative Health (NCCIH). Tea Tree Oil. Read 2026-10-23.
- Pet Poison Helpline. Tea Tree Oil. Read 2026-10-23.
- de Groot AC, Schmidt E. Contact Dermatitis. 2016. Tea tree oil: contact allergy and chemical composition. (abstract read via PubMed). Read 2026-10-23.
- U.S. Food and Drug Administration. Aromatherapy. Read 2026-10-23.
- National Association for Holistic Aromatherapy (NAHA). Safety. Read 2026-10-23.
- Kaddu S et al. J Am Acad Dermatol. 2001. Accidental bullous phototoxic reactions to bergamot aromatherapy oil. (abstract read via PubMed). Read 2026-10-23.
- National Center for Complementary and Integrative Health (NCCIH). Chamomile. Read 2026-10-23.
- Larsen W et al. Contact Dermatitis. 2001. Fragrance contact dermatitis: a worldwide multicenter investigation (Part II). (abstract read via PubMed). Read 2026-10-23.
- Geier J et al. Contact Dermatitis. 2022. Contact sensitization to essential oils: IVDK data of the years 2010-2019. (abstract read via PubMed). Read 2026-10-23.
- EFSA FEEDAP Panel. EFSA J. 2023. Safety and efficacy of a feed additive consisting of an essential oil derived from the aerial parts of Cymbopogon flexuosus for use in all animal species. (abstract read via PubMed). Read 2026-10-23.
- EFSA FEEDAP Panel. EFSA J. 2024. Safety and efficacy of a feed additive consisting of an essential oil obtained from the wood of Juniperus deppeana (cedarwood Texas oil) for use in all animal species. (abstract read via PubMed). Read 2026-10-23.
- European Medicines Agency (EMA), HMPC. Community herbal monograph on Juniperus communis L., aetheroleum (EMA/HMPC/12402/2010). 2011. Read 2026-10-23.
- European Medicines Agency (EMA). Myrrha - herbal medicinal product. Read 2026-10-23.
- EFSA FEEDAP Panel. EFSA J. 2025. Safety and efficacy of a feed additive consisting of an essential oil derived from the leaves of Pogostemon cablin (patchouli oil) for use in all animal species. (abstract read via PubMed). Read 2026-10-23.
- Welker JA, Zaloga GP. Chest. 1999. Pine oil ingestion: a common cause of poisoning. (abstract read via PubMed). Read 2026-10-23.
- Brook MP et al. Ann Emerg Med. 1989. Pine oil cleaner ingestion. (abstract read via PubMed). Read 2026-10-23.
- Khine H et al. Pediatrics. 2009. A cluster of children with seizures caused by camphor poisoning. (abstract read via PubMed). Read 2026-10-23.
- National Center for Complementary and Integrative Health (NCCIH). Cinnamon. Read 2026-10-23.
- Janes SE et al. Eur J Pediatr. 2005. Essential oil poisoning: N-acetylcysteine for eugenol-induced hepatic failure and analysis of a national database. (abstract read via PubMed). Read 2026-10-23.
- NIH LiverTox (NIDDK). Pennyroyal Oil. 2020 entry. (abstract read via PubMed). Read 2026-10-23.
- Davis JE. J Emerg Med. 2007. Are one or two dangerous? Methyl salicylate exposure in toddlers. (abstract read via PubMed). Read 2026-10-23.
- Chan TY. Hum Exp Toxicol. 1996. Potential dangers from topical preparations containing methyl salicylate. (abstract read via PubMed). Read 2026-10-23.
Education, not medical advice. This page is for general information. It does not diagnose or treat any condition and is not a substitute for care from a qualified health professional. Natural does not automatically mean safe. Ask a clinician or pharmacist before changing your care, especially if you take medication, are pregnant or breastfeeding, or have a health condition.