Thyme (Thymus vulgaris)
Natural Standard Bottom Line Monograph, Copyright © 2013 (www.naturalstandard.com). Commercial distribution prohibited. This monograph is intended for informational purposes only, and should not be interpreted as specific medical advice. You should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.
While some complementary and alternative techniques have been studied scientifically, high-quality data regarding safety, effectiveness, and mechanism of action are limited or controversial for most therapies. Whenever possible, it is recommended that practitioners be licensed by a recognized professional organization that adheres to clearly published standards. In addition, before starting a new technique or engaging a practitioner, it is recommended that patients speak with their primary healthcare provider(s). Potential benefits, risks (including financial costs), and alternatives should be carefully considered. The below monograph is designed to provide historical background and an overview of clinically-oriented research, and neither advocates for or against the use of a particular therapy.
Acetophenone glycosides, Acinos alpinus, alpha-terpinene, alpine thyme inflorescences, (-)-angelicoidenol-beta-D-glucopyranoside, Ankaferd blood stopper®, apigenin, black thyme, borneol, camphor, carvacrol, Cervitec®, cineole, cis-myrtanol, common garden thyme, common thyme, creeping thyme, English thyme, epoxythymol-diesters, eriodictyol, essential oil, ethyl-N-dimethyl ether of thymol fumarate, farigola, flavones, flavonoids, folia Thymi, French thyme, gamma-terpinene, garden thyme, Gartenthymian (German), geraniol thyme, glucopyranoside, glucopyranosylthymoquinol, herba Thymi, herba timi, hydroxyjasmone, Iberian thymus, iodine, iodinized oil of thymol, iodized thymol, iron, Jeju, kochi thyme, Labiatae (family), Lamiaceae (family), linalool, luteolin, luteolin 7-glucuronide, mercury thymol (merthiolate), Moroccan endemic thyme, mother of thyme, N-thymol compounds, oleanolic acid, oxalate, para-methyl-isopropyl-phenol, paramethyl-isopropyl-phenol, p-cymene, phenols, quinine thymolate, red thyme, rosmarinic acid, (R)-p-cymen-9-yl beta-D-glucopyranoside, rubbed thyme, salicylates, saponins, Sardinian thymus, serpyllium, shepherd's thyme, silver thymol sulfone, Spanish thyme, Spanish thyme oil, tannins, taxifolin, ten, tepal (thymol ester of palmitic acid), terpenoids, terpinyl acetate, thick leaf thyme, THPI, thym (French), thyme aetheroleum, thyme honey, thyme oil, thyme red, thyme red oil, thyme white essential oil, thyme white oil, Thymi herba, Thymian (German), thymodihydroquinone, thymodrosine balsam, thymodrosine suppositories, thymol, thymol glucuronide, thymol iodide, thymol iodine, thymol-p-phenylazobenzoate, thymol silver sulfone, thymol-sodium hypochlorite, thymol sulfone silver salt, thymol-sulfuric acid, thymolan, Thymus aureopunctatus, Thymus broussonetii, Thymus caespititius, Thymus capitatus, Thymus caramanicus, Thymus cilicicus, Thymus citriodorus, Thymus daenensis, Thymus eigii, Thymus eriocalyx, Thymus fontanesii, Thymus hyemalis, Thymus hyemalis, Thymus kotschyanus, Thymus longicaulis, Thymus longicaulis subsp. chaubardii var. chaubardii, Thymus longicaulis subsp. longicaulis var. subisophyllus, Thymus macedonicus, Thymus magnus, Thymus malyi, Thymus marshallianus, Thymus mastichina, Thymus mongolicus, Thymus numidicus, Thymus origanium, Thymus pectinatus, Thymus persicus, Thymus piperella, Thymus polytrichus, Thymus praecox, Thymus pubescens, Thymus pulegioides, Thymus pulvinatus, Thymus quinquecostatus, Thymus richardii, Thymus serpylloides ssp. gadorensis, Thymus serpyllum, Thymus serpyllum ssp. tanaenis, Thymbra spicata, Thymus tosevii, Thymus x-porlock, Thymus zygis, Thymus zygioides var. lycaonicus, time, timo, TV-3-IIIA-IIa, ursolic acid, white thyme oil, wild thyme, wild thyme hydrosol, wild thyme oil.
Note: There are up to 400 subspecies of thyme. Common thyme (Thymus vulgaris) and Spanish thyme (Thymus zygis) are often used interchangeably for medicinal purposes. Common thyme is not to be confused with calamint (calamintha ascendens, basil thyme), thyme basil (Acinos suaveolens), cat thyme (Teucrium polium), mountain thyme (Hedeoma multiflora Benth.), water thyme (Hydrilla verticillata), Spanish Origanum majorana (Thymus mastichina), or with Spanish origanum oil (Thymus capitatus, Sicilian thyme, Spanish thyme). This monograph is primarily concerned with Thymus vulgaris, although other species may be mentioned when summarizing the relevant literature.
Thyme (Thymus vulgaris) is a perennial subshrub native to the Mediterranean and commercially cultivated in many European countries, as well as Morocco and the United States. Thyme is also collected wild from European countries, such as Albania and Bulgaria. Spanish thyme (Thymus zygis) is often used interchangeably with Thymus vulgaris for medicinal purposes.
Thyme has been used medicinally for thousands of years. Beyond its common culinary application, it has been used for many indications, based upon proposed antimicrobial, antitussive, spasmolytic, and antioxidant activity. Thymol, one of the constituents of thyme, is contained in antiseptic mouthwashes, with limited supportive evidence for reductions in plaque formation, gingivitis, and caries.
Traditional uses of thyme include coughs and upper respiratory congestion, and it continues to be one of the most commonly recommended herbs in Europe for these indications. The German Commission E (expert panel) has approved thyme for symptoms of bronchitis, whooping cough, and catarrh (inflammation of upper respiratory tract mucous membranes).
Experts have recommended the use of thymol in treatment of actinomycosis (lumpy jaw disease), onycholysis (separation or loosening of a fingernail or toenail from its nail bed), and paronychia (inflammation of the tissue surrounding a fingernail or toenail), due to its antifungal properties.
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Agitation in dementia
In preliminary research, thyme essential oil in aromatherapy, in combination with massage, was not shown to have an effect on agitation in patients with dementia. Further research is needed.
Alopecia areata (hair loss)
There is currently insufficient data on the use of topical thyme oil for alopecia areata. Combination preparations of essential oils including thyme have been evaluated, without definitive results. Research is needed using thyme alone (not in any combination products).
Bronchitis / cough
Thyme has traditionally been used for the treatment of respiratory conditions, including cough and bronchitis. The German Commission E (expert panel) has approved thyme for use in bronchitis. However, due to a lack of available data evaluating thyme alone (and not in any combination products), additional study is needed to make a conclusion.
One of thyme's main constituents, thymol, has been shown to have antibacterial effects. Thymol is included as one of several ingredients in antiseptic mouthwashes such as Listerine®. Clinical studies have reported efficacy of Listerine® in decreasing plaque formation and gingivitis, although human evidence for thymol alone is limited. Further research is needed.
Inflammatory skin disorders
Historically, thyme has been used topically for a number of skin conditions. Results of available studies are inconclusive. Additional research is needed in this area.
*Key to grades:A: Strong scientific evidence for this use; B: Good scientific evidence for this use; C: Unclear scientific evidence for this use; D: Fair scientific evidence against this use (it may not work); F: Strong scientific evidence against this use (it likely does not work).
The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious and should be evaluated by a qualified health care professional.
Abscess, acaricidal (lethal effects on mites), acne, alcohol abuse, altitude sickness, Alzheimer's disease, anesthetic, anthrax, antibacterial, anticonvulsant, antifungal, antioxidant, antiseptic, antispasmodic, antiviral, anxiety, appetite stimulant, aromatherapy, arthritis, asthma, bad breath, bedwetting, blood disorders, burns, cancer, catarrh (throat), cellulitis (skin inflammation), cholera, chronic obstructive pulmonary disease, colic, cosmetic uses, cystitis (bladder infection), dental conditions, depression, dermatitis (skin condition), dermatomyositis (immune response to skin and muscle), diarrhea, disease diagnosis, diuresis (increased urine), dyslexia, dysmenorrhea (painful menstruation), dyspepsia (upset stomach), dyspnea (shortness of breath), ear wax removal, edema (swelling), emmenagogue (to stimulate menstruation), enuresis (inability to control urination), epilepsy, expectorant, eye problems, fever, flu, food preservative, gas, gastritis (inflammation of the stomach), gingivitis, glaucoma, gout (foot inflammation), H. pylori, headache, heartburn, hepatitis (liver disease), herpes, high cholesterol, hookworms, immune function, inflammation, insect bites, insecticidal, insomnia, Kaposi's sarcoma, laryngitis, lice, liver disease, malaria, mastitis, methicillin-resistant Staphylococcus aureus (MRSA), mosquito repellant, neuralgia (nerve pain), nightmares, obesity, osteoporosis, otitis media (ear infection), pain, parasites and worms, paronychia / onycholysis / antifungal, pertussis (whooping cough), pruritus (severe itching), respiratory tract infections, scabies, scleroderma (chronic degenerative disease that affects the joints, skin, and internal organs), sickle cell anemia, sinusitis, skin cancer, sore throat, spasms, sprains, stomach cramps, stomatitis (mouth sores), swelling (topical), systemic lupus erythematosus, tonsillitis, tuberculosis, urethritis (inflammation of the urethra), urinary tract infection, vaginal disorders (lichen sclerosis), vaginal irritation, viral encephalitis (brain inflammation due to a virus), warts, whooping cough, wound healing.
The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
Adults (18 years and older)
There is no proven safe or effective dose for thyme or thymol in adults. Thyme has been taken by mouth as a tea, liquid extract, and tincture. On the skin, ointments and compresses have been used. Thyme oil is considered to be highly toxic and should not be taken internally.
For cough, syrup of thyme has been taken by mouth for five days.
For upper respiratory tract infection, traditional uses include drinking tea, made by steeping 1-2 grams of dried herb in 150 milliliters of boiling water for 10 minutes, several times daily as needed for symptom alleviation. Other examples include 1-2 grams of extract in fluid or one cup of water up to three times daily; 20-40 drops of liquid extract (1:1 weight/volume of fresh leaf or 1:4 of dried leaf) three times daily in juice; or 40 drops of tincture (1:10 in 70% ethanol) up to three times daily.
For agitation in dementia, thyme oil placed on an absorbent fabric sachet and pinned near the collarbone every three hours for two weeks has been used.
Children (younger than 18 years)
There is no proven safe or effective dose for thyme in children.
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Avoid in individuals with a known allergy or hypersensitivity to thyme, its constituents, members of the Lamiaceae (mint) family, or to rosemary (Rosmarinus officinalis).
Cross-reactions to birch pollen, celery, oregano, and other species in the Lamiaceae or Labiatae (mint) families may occur. Symptoms of allergy may include nausea, vomiting, runny nose, severe itching, swelling under the skin, difficulty swallowing, altered voice, low blood pressure, contact dermatitis, inflammation of lung cells, and progressive respiratory difficulty. Occupational asthma has been reported.
Side Effects and Warnings
Although not well studied in humans, thyme flowers and leaves appear to be safe in culinary and in limited medicinal use. Caution is warranted with the use of thyme oil, which should not be taken by mouth and should be diluted when applied on the skin, due to potentially toxic effects.
Side effects of thyme taken by mouth may include headache, dizziness, low blood pressure, slowed heart rate, heartburn, nausea, vomiting, diarrhea, gastrointestinal irritation, muscle weakness, and worsened inflammation associated with urinary tract infections.
Taking thyme oil by mouth may cause seizure, coma, cardiac arrest, or respiratory arrest. High doses of thyme or thyme oil may cause rapid breathing. Inflammation of the eye and nasal mucosa has also been reported with exposure to thyme dust. Halothane hepatitis (liver disease) may be partially due to the thymol in the halothane. Thyme extract may alter levels of certain blood cells.
Thyme may lower blood sugar levels. Caution is advised in patients with diabetes or hypoglycemia and in those taking drugs, herbs, or supplements that affect blood sugar. Blood glucose levels may need to be monitored by a qualified healthcare professional, including a pharmacist. Medication adjustments may be necessary.
Thyme may increase the risk of bleeding. Caution is advised in patients with bleeding disorders or those taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary.
Use cautiously in patients with gastrointestinal irritation or peptic ulcer disease.
Thyme may cause low blood pressure. Caution is advised in patients with low blood pressure and in those taking drugs, herbs, or supplements that lower blood pressure.
Drowsiness or sedation may occur. Use caution if driving or operating heavy machinery or if taking sedatives or CNS depressants.
Caution is advised when thyme is used in medicinal amounts in women who are pregnant or trying to become pregnant, due to the possibility of negative effects on fertility and/or potential to stimulate abortion.
Use cautiously in patients with thyroid disorders, hormonal disorders or at risk for hormone imbalances, or in patients taking agents for these conditions.
Use cautiously in patients taking agents metabolized by the liver's cytochrome P450 system, ciprofloxacin, salicylate-containing agents, or topical agents.
Avoid in individuals with a known allergy or hypersensitivity to thyme, its constituents, members of the Lamiaceae (mint) family, or to rosemary (Rosmarinus officinalis).
Avoid use on the skin in areas of skin breakdown or injury, or in atopic patients.
Pregnancy and Breastfeeding
Medicinal levels of thyme are not recommended in pregnant or breastfeeding women, due to a lack of available scientific evidence. Thyme may act as an emmenagogue (promoting menstruation) and abortifacient (promoting abortion).
Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.
Interactions with Drugs
Thyme may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants (blood thinners) such as warfarin (Coumadin®) or heparin, antiplatelet drugs such as clopidogrel (Plavix®), and nonsteroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®).
Thyme may lower blood sugar levels. Caution is advised when using medications that may also lower blood sugar. Patients taking insulin or drugs for diabetes by mouth should be monitored closely by a qualified healthcare professional, including a pharmacist. Medication adjustments may be necessary.
Thyme may interfere with the way the body processes certain drugs using the liver's cytochrome P450 enzyme system. As a result, the levels of these drugs may be increased in the blood and may cause increased effects or potentially serious adverse reactions. Patients using any medications should check the package insert and speak with a qualified healthcare professional, including a pharmacist, about possible interactions.
Thyme may cause low blood pressure. Caution is advised in patients taking drugs that lower blood pressure.
Thyme may increase the amount of drowsiness caused by some drugs. Examples include benzodiazepines such as lorazepam (Ativan®) or diazepam (Valium®), barbiturates such as phenobarbital, narcotics such as codeine, some antidepressants, central nervous system depressants, sedatives, and alcohol. Caution is advised while driving or operating machinery.
Thyme may also interact with 5-fluorouracil, Alzheimer's agents, analgesics (pain relievers), antibiotics, anticancer agents, antifungals, anti-inflammatory agents, antiprotozoals, antispasmodic agents, antithyroid agents, antivirals, bethanechol, bosentan, caffeine, cardiovascular agents, cholesterol-lowering agents, cholinesterase inhibitors, cough medications, dental agents, drugs that affect GABA, drugs used for osteoporosis, hormonal agents, hydrocortisone, hydrophilic drugs, immune suppressants, ketoprofen, muscle relaxants, naproxen, nitrendipine, piroxicam, salicylates, tamoxifen, thyroid hormones, and vasodilators (agents that increase dilation of blood vessels).
Interactions with Herbs and Dietary Supplements
Thyme may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba, and fewer cases with garlic and saw palmetto. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases.
Thyme may lower blood sugar levels. Caution is advised when using herbs or supplements that may also lower blood sugar. Blood glucose levels may require monitoring, and doses may need adjustment.
Thyme may interfere with the way the body processes certain herbs or supplements using the liver's cytochrome P450 enzyme system. As a result, the levels of other herbs or supplements may become too high in the blood. It may also alter the effects that other herbs or supplements possibly have on the P450 system.
Thyme may cause low blood pressure. Caution is advised in patients taking herbs and supplements that lower blood pressure.
Thyme may increase the amount of drowsiness caused by some herbs or supplements such as central nervous system depressants and sedatives.
Thyme may also interact with agar, Alzheimer's herbs and supplements, analgesics (pain relievers), antibacterials, anticancer herbs and supplements, antifungals, anti-inflammatory herbs and supplements, antioxidants, antiparasitics, antispasmodics, antivirals, anxiolytics, basil, caffeine, cardioactive herbs and supplements, carrageenan, cholesterol-lowering herbs and supplements, dental herbs and supplements, fatty acids, fenugreek, grape juice, herbs and supplements that affect GABA, herbs and supplements that affect the thyroid, herbs and supplements used for osteoporosis, herbs and supplements used for cough, hormonal herbs and supplements, hydrophilic herbs and supplements, immune suppressants, iron, ivy, muscle relaxants, oregano, potato, probiotics, rice, rosemary, sage, salicylate-containing herbs and supplements, shrimp, soy sauce, sunflower oil, vasorelaxants (herbs and supplements that increase dilation of blood vessels), vitamin E, and xanthum gum.
This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to www.naturalstandard.com. Selected references are listed below.
Anderson C, Lis-Balchin M, Kirk-Smith M. Evaluation of massage with essential oils on childhood atopic eczema. Phytother Res 2000; 14(6):452-6. View Abstract
Aschhoff B. Retrospective study of Ukrain treatment in 203 patients with advanced- stage tumors. Drugs Exp Clin Res 2000;26(5-6):249-252. View Abstract
Baca P, Munoz MJ, Bravo M, et al. Effectiveness of chlorhexidine-thymol varnish for caries reduction in permanent first molars of 6-7-year-old children: 24-month clinical trial. Community Dent Oral Epidemiol 2002;30(5):363-368. View Abstract
Charles CH, Sharma NC, Galustians HJ, et al. Comparative efficacy of an antiseptic mouthrinse and an antiplaque/antigingivitis dentifrice. A six-month clinical trial. J Am Dent Assoc 2001;132(5):670-675. View Abstract
Dapkevicius A, van Beek TA, Lelyveld GP, et al. Isolation and structure elucidation of radical scavengers from Thymus vulgaris leaves. J Nat Prod 2002;65(6):892-896. View Abstract
Fine DH, Furgang D, Barnett ML. Comparative antimicrobial activities of antiseptic mouthrinses against isogenic planktonic and biofilm forms of Actinobacillus actinomycetemcomitans. J Clin Periodontol 2001;28(7):697-700. View Abstract
Haukali G, Poulsen S. Effect of a varnish containing chlorhexidine and thymol (Cervitec) on approximal caries in 13- to 16-year-old schoolchildren in a low caries area. Caries Res 2003;37(3):185-189. View Abstract
Hay IC, Jamieson M, Ormerod AD. Randomized trial of aromatherapy. Successful treatment for alopecia areata. Arch Dermatol 1998;134(11):1349-1352. View Abstract
Knols G, Stal PC, Van Ree JW. Productive coughing complaints: Sirupus Thymi or Bromhexine? A double-blind randomized study. Huisarts en Wetenschap 1994;37:392-394.
Miura K, Kikuzaki H, Nakatani N. Antioxidant activity of chemical components from sage (Salvia officinalis L.) and thyme (Thymus vulgaris L.) measured by the oil stability index method. J Agric Food Chem 2002;50(7):1845-1851. View Abstract
Nostro A, Blanco AR, Cannatelli MA, et al. Susceptibility of methicillin-resistant staphylococci to oregano essential oil, carvacrol and thymol. FEMS Microbiol Lett 2004;230(2):191-195. View Abstract
Shapiro S, Meier A, Guggenheim B. The antimicrobial activity of essential oils and essential oil components towards oral bacteria. Oral Microbiol Immunol 1994; 9(4):202-8. View Abstract
Snow LA, Hovanec L, Brandt J. A controlled trial of aromatherapy for agitation in nursing home patients with dementia. J Altern Complement Med 2004; 10(3):431-7. View Abstract
Westermeyer RR, Terpolilli RN. Cardiac asystole after mouthwash ingestion: a case report and review of the contents. Mil Med 2001;166(9):833-835. View Abstract
Youdim KA, Deans SG. Effect of thyme oil and thymol dietary supplementation on the antioxidant status and fatty acid composition of the ageing rat brain. Br J Nutr 2000;83(1):87-93. View Abstract
Copyright © 2013 Natural Standard (www.naturalstandard.com)
The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.
March 22, 2017