Drug & supplement interaction

Thyme + Finasteride

Finasteride brand names: Propecia, Proscar.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 27, 2026
The bottom line No known interaction

We found no known interaction between Thyme and Finasteride in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Thyme and Finasteride

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Finasteride and Thyme in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Thyme safety at a glance

Thyme overall Use caution Generally safe as a food and in tea, but the concentrated essential oil can be toxic if swallowed.
Pregnancy Likely Safe When used in amounts commonly found in foods. Thyme has Generally Recognized as Safe (GRAS) status in the US. There is insufficient reliable information availab... Read the full pregnancy detail
Breastfeeding Likely Safe When used in amounts commonly found in foods. Thyme has Generally Recognized as Safe (GRAS) status in the US. There is insufficient reliable information availab... Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Finasteride and Thyme? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Finasteride

Interactions in our licensed database are recorded against drug classes, not just single drug names. Finasteride is filed under 3 classifications — including cytochrome p450 3a4 (cyp3a4) substrates, oral drugs. Thyme has documented interactions with 4 drug classes — the most serious being anticholinergic drugs (moderate), anticoagulant/antiplatelet drugs (moderate) and cholinergic drugs (moderate) — and none of Finasteride’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Thyme Does Interact With Other Medications

Thyme has 379 moderate known drug interactions in our database — Finasteride isn’t one of them. If you take anything else, check it against the full list below.

Moderate 379 No known interaction 2,451 (incl. Finasteride)
Taking anything else?

Check Another of Your Medications Against Thyme

Covers the 2,830 medications we’ve checked against Thyme. Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests Thyme and Finasteride May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. One of them is worth acting on rather than waiting out — marked below.

  • An allergic reaction Worth acting on Additional detail

    Thyme

    “Orally, thyme is well tolerated when used in food and seems to be well tolerated when used medicinally. Topically, thyme seems to be generally well tolerated.

    Most Common Adverse Effects:

    Orally: Allergic reactions, diarrhea, dizziness, headache, heartburn, nausea, or vomiting.

    Topically: Contact dermatitis and skin irritation.”

    Thyme · Natural Medicines adverse-effect record, reported in cluster headache.

    Finasteride

    Listed in the ADVERSE REACTIONS section of the FDA label for Finasteride. Read the label on DailyMed ›

  • Dizziness / Headache Additional detail

    Thyme

    “Orally, thyme may case headache or dizziness.”

    Thyme · Natural Medicines adverse-effect record, reported in cluster headache.

    1 source cited
    1. 94033. Erol S, Aydin B, Dilli D, Okumus N, Zenciroglu A, Gündüz M. An interesting newborn case of fructose 1-6 diphosphatase deficiency triggered after thyme juice ingestion. Clin Lab. 2014;60(1):151-3. PubMed

    Finasteride

    Listed in the ADVERSE REACTIONS section of the FDA label for Finasteride. Read the label on DailyMed ›

  • A skin rash Additional detail

    Thyme

    “Topically, thyme, thyme oil, or the constituent thymol can cause contact dermatitis and skin irritation. In one study of 100 patients with contact allergies, 5% were attributed to thyme oil as an allergen contained in wound dressings. Toothpastes containing thymol have been associated with cheilitis and glossitis.”

    Thyme · Natural Medicines adverse-effect record, reported in allergic rhinitis (hay fever).

    6 sources cited
    1. 13463. Spiewak R, Skorska C, Dutkiewicz J. Occupational airborne contact dermatitis caused by thyme dust. Contact Dermatitis 2001;44:235-9. . PubMed
    2. 78252. Cuzzolin, L. and Benoni, G. Attitudes and knowledge toward natural products safety in the pharmacy setting: an Italian study. Phytother.Res 2009;23(7):1018-1023. PubMed
    3. 78362. Le Roy, R., Grosshans, E., and Foussereau, J. [Investigation of contact allergies in 100 cases of ulcus cruris (author's transl)]. Derm.Beruf.Umwelt. 1981;29(6):168-170.
    4. 78384. Lorenzi, S., Placucci, F., Vincenzi, C., Bardazzi, F., and Tosti, A. Allergic contact dermatitis due to thymol. Contact Dermatitis 1995;33(6):439-440. PubMed
    5. 77982. Mackiewicz, B., Skorska, C., Dutkiewicz, J., Michnar, M., Milanowski, J., Prazmo, Z., Krysinska-Traczyk, E., and Cisak, E. Allergic alveolitis due to herb dust exposure. Ann Agric Environ Med 1999;6(2):167-170.
    6. 78154. Martinez-Gonzalez, M. C., Goday Bujan, J. J., Martinez, Gomez W., and Fonseca, Capdevila E. Concomitant allergic contact dermatitis due to Rosmarinus officinalis (rosemary) and Thymus vulgaris (thyme). Contact Dermatitis 2007;56(1):49-50.

    Finasteride

    Listed in the ADVERSE REACTIONS section of the FDA label for Finasteride. Read the label on DailyMed ›

Reported for Thyme but not commonly for Finasteride: stomach upset, heartburn, vomiting and diarrhea.

Effects for Finasteride come from the ADVERSE REACTIONS section of its FDA label; effects for Thyme come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Thyme in Pregnancy & Breastfeeding

Pregnancy And Lactation Likely Safe

When used in amounts commonly found in foods. Thyme has Generally Recognized as Safe (GRAS) status in the US. There is insufficient reliable information available about the safety of thyme when used in medicinal amounts during pregnancy and breast-feeding; avoid using.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

From our Q&A

Questions About Thyme or Finasteride

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Thyme or Finasteride, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Finasteride

This page covers Thyme only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Finasteride page lists 138 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate) and Adrafinil (moderate).

By severity: 3 major · 94 moderate · 41 minor.

From our pharmacist’s overview on the Finasteride page

“The supplement list for finasteride (Propecia, Proscar) is one I would read carefully rather than skim, because three of its 138 entries are rated major. Almost everything here works through the same liver enzyme, CYP3A4, that clears finasteride.”

Reviewed by 2 · Jul 18, 2026

Open the Finasteride interaction page

One more smart check

Taking Thyme as Part of a Dietary Supplement Product? Check It for Interactions

We hold 708 real supplement products containing Thyme, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Thyme. Even though Thyme itself has no known interaction with Finasteride, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Thyme and Finasteride Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Thyme
Top 25%

#199 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Finasteride
Top 25%

#355 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Thyme reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 27, 2026. The Thyme and Finasteride records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Thyme

What is Thyme?

Thyme
  • Cough and respiratory congestion
  • Sore throat
  • Digestive upset
  • Antimicrobial and antiseptic uses
  • Flavoring in cooking

Thyme is a common kitchen herb that has long been used for coughs, sore throats, and digestive complaints. It is generally safe in the amounts found in food, and some cough products that combine thyme with other herbs have modest supporting evidence, but high-quality research on thyme alone is limited. The concentrated essential oil should never be swallowed undiluted.

Thymus vulgaris · Lamiaceae · Leaves, flowering tops, and essential oil · Tea, dried herb, liquid extract, capsules, essential oil, syrups, and lozenges

An interaction check asks whether these two react with each other — it does not ask whether Thyme is a good idea for someone in your situation. Here is what our Thyme record says about it on its own.

Thyme: dosing

There is no official standardized dose for thyme. The right amount depends on the form you are using, such as tea, extract, or a combination cough product.The safest approach is to follow the directions on the product label and not exceed them.

From our Thyme monograph — the full record covers uses, side effects and every documented interaction.

Read the full Thyme monograph & all interactions
Medication

About Finasteride

What Is Finasteride Used For?

Brand names: Propecia, Proscar

Finasteride tablets are used in men for two main purposes, depending on the product. Which one you take depends on the strength and brand your prescriber chose.

Enlarged prostate (BPH): Proscar and finasteride tablets labeled for BPH treat symptomatic BPH in men with an enlarged prostate. They improve symptoms and reduce the risk of acute urinary retention (suddenly being unable to urinate). They also reduce the risk of needing surgery such as TURP or prostatectomy. With the alpha-blocker doxazosin, they reduce the risk of BPH symptoms getting worse. They are not approved to prevent prostate cancer.

Male pattern hair loss: Propecia and finasteride tablets labeled for hair loss treat male pattern hair loss (androgenetic alopecia) in men only. Efficacy in bitemporal recession (receding at the temples) has not been established. These products are not for use in women.

Most-Reported Side Effects for Finasteride

From FAERS, the FDA’s public side-effect reporting system (59,984 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Erectile dysfunction 4,195 reports
Fatigue 4,093 reports
Depression 3,674 reports
Anxiety 3,092 reports
Adverse drug reaction 2,768 reports
See full Finasteride drug information
Keep checking

Other Drugs & Thyme

Browse every other medication we’ve checked against Thyme — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
379Moderate
0Minor
2,450No known interaction
379 Moderate 2,450 No interaction
Moderate

379 interactions

Showing 60 of 379 moderate interactions — see all 379 on the Thyme page.

No interaction 2,450 drugs checked — show the list

We also checked Thyme against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,450 medications checked with no known interaction — see the full Thyme list.

See the full Thyme interactions page
See every supplement checked against Finasteride, ranked by severity
Evidence & sources

Thyme References

The 18 references that drive our Thyme monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Zava DT, Dollbaum CM, Blen M. Estrogen and progestin bioactivity of foods, herbs, and spices. Proc Soc Exp Biol Med 1998;217:369-78. PubMed
  2. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
  3. Okazaki K, Kawazoe K, Takaishi Y. Human platelet aggregation inhibitors from thyme (Thymus vulgaris L.). Phytother Res 2002;16:398-9. .
  4. Spiewak R, Skorska C, Dutkiewicz J. Occupational airborne contact dermatitis caused by thyme dust. Contact Dermatitis 2001;44:235-9. . PubMed
  5. Ernst E, Marz R, Sieder C. A controlled multi-centre study of herbal versus synthetic secretolytic drugs for acute bronchitis. Phytomedicine 1997;4:287-93. PubMed
  6. Yamamoto J, Yamada K, Naemura A, et al. Testing various herbs for antithrombotic effect. Nutrition 2005;21(5):580-7. PubMed
  7. Tognolini, M., Barocelli, E., Ballabeni, V., Bruni, R., Bianchi, A., Chiavarini, M., and Impicciatore, M. Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity. Life Sci. 2-23-2006;78(13):1419-1432. PubMed
  8. Mackiewicz, B., Skorska, C., Dutkiewicz, J., Michnar, M., Milanowski, J., Prazmo, Z., Krysinska-Traczyk, E., and Cisak, E. Allergic alveolitis due to herb dust exposure. Ann Agric Environ Med 1999;6(2):167-170.
  9. Martinez-Gonzalez, M. C., Goday Bujan, J. J., Martinez, Gomez W., and Fonseca, Capdevila E. Concomitant allergic contact dermatitis due to Rosmarinus officinalis (rosemary) and Thymus vulgaris (thyme). Contact Dermatitis 2007;56(1):49-50.
  10. Jukic, M., Politeo, O., Maksimovic, M., Milos, M., and Milos, M. In vitro acetylcholinesterase inhibitory properties of thymol, carvacrol and their derivatives thymoquinone and thymohydroquinone. Phytother.Res 2007;21(3):259-261.
  11. Marzian, O. [Treatment of acute bronchitis in children and adolescents. Non-interventional postmarketing surveillance study confirms the benefit and safety of a syrup made of extracts from thyme and ivy leaves]. MMW.Fortschr.Med 6-28-2007;149(27-28 Suppl
  12. Cuzzolin, L. and Benoni, G. Attitudes and knowledge toward natural products safety in the pharmacy setting: an Italian study. Phytother.Res 2009;23(7):1018-1023. PubMed
  13. Berova, N., Stransky, L., and Krasteva, M. Studies on contact dermatitis in stomatological staff. Dermatol.Monatsschr. 1990;176(1):15-18.
  14. Smeenk, G., Kerckhoffs, H. P., and Schreurs, P. H. Contact allergy to a reaction product in Hirudoid cream: an example of compound allergy. Br.J Dermatol. 1987;116(2):223-231.
  15. Le Roy, R., Grosshans, E., and Foussereau, J. [Investigation of contact allergies in 100 cases of ulcus cruris (author's transl)]. Derm.Beruf.Umwelt. 1981;29(6):168-170.

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Thyme and Finasteride Together: Common Questions

Is it safe to take Thyme with Finasteride?
We do not list a known interaction between Thyme and Finasteride. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Do Thyme and Finasteride have any of the same side effects?
Yes — our sources link each of them separately to 4 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
How was the Thyme and Finasteride combination checked?
Interactions in our licensed database are recorded against drug classes. Finasteride is filed under 3 classifications, and Thyme has documented interactions with 4 drug classes — none of Finasteride's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Thyme interact with any other medications?
Yes. Thyme has 379 documented drug interactions in our database — Finasteride is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Finasteride interact with any supplements?
Yes. Finasteride has documented interactions with 138 supplements in our database — Thyme is not one of them. The Finasteride interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Where next

Keep Exploring

Thyme monograph Uses, safety profile, and every drug interaction in one place Finasteride drug information The full plain-English guide to this medication Finasteride supplement interactions Every supplement checked against Finasteride, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 18 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Finasteride and Thyme?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.