Drug & supplement interaction

Bay Leaf + Sulfamethoxazole, Trimethoprim

Sulfamethoxazole, Trimethoprim brand names: Bactrim, Bactrim DS, Cotrim DS, Septra, Septra DS, and others.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 13, 2026
The bottom line No known interaction

We found no known interaction between Bay Leaf and Sulfamethoxazole, Trimethoprim 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.

Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Bay Leaf and Sulfamethoxazole, Trimethoprim

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 Sulfamethoxazole, Trimethoprim and Bay Leaf 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.

Bay Leaf safety at a glance

Bay Leaf overall Use caution Safe as a food seasoning, but concentrated supplements and essential oil are less studied.
Pregnancy Use caution Food amounts are likely fine, but avoid medicinal or large amounts due to limited safety data.
Breastfeeding Use caution Food amounts are likely fine, but avoid medicinal doses because safety is not well studied.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Sulfamethoxazole, Trimethoprim and Bay Leaf? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Sulfamethoxazole, Trimethoprim

Interactions in our licensed database are recorded against drug classes, not just single drug names. Sulfamethoxazole, Trimethoprim is filed under 9 classifications — including sulfonamide antibiotics, cytochrome p450 2c9 (cyp2c9) inhibitors, cytochrome p450 2c9 (cyp2c9) substrates. Bay Leaf has documented interactions with 3 drug classes — the most serious being antidiabetes drugs (moderate), cns depressants (moderate) and narcotic drugs (moderate) — and none of Sulfamethoxazole, Trimethoprim’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

Bay Leaf Does Interact With Other Medications

Bay Leaf has 335 moderate known drug interactions in our database — Sulfamethoxazole, Trimethoprim isn’t one of them. If you take anything else, check it against the full list below.

Moderate 335 No known interaction 2,495 (incl. Sulfamethoxazole, Trimethoprim)
Taking anything else?

Check Another of Your Medications Against Bay Leaf

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

What to actually watch for

No Interaction Found — But Data Suggests Bay Leaf and Sulfamethoxazole, Trimethoprim 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

    Bay Leaf

    “Orally, bay leaf is well tolerated when used in amounts found in foods and seems to be well tolerated when the leaf powder is used as medicine. However, the whole, intact leaf can cause severe adverse effects.”

    Bay Leaf · Natural Medicines adverse-effect record, reported in dermatitis.

    “Bay leaf can cause allergic reactions, including contact dermatitis. In one case, allergic contact dermatitis occurred with a positive skin test after use of a massage oil containing bay leaf. Another patient developed erythematous plaques on the elbow after applying bay leaves with a topical occlusion for 2 days. The dermatitis resolved after a two-week course of topical corticosteroids.”

    Bay Leaf · Natural Medicines adverse-effect record, reported in dermatitis.

    4 sources cited
    1. 15571. Adisen E, Onder M. Allergic contact dermatitis from Laurus nobilis oil induced by massage. Contact Dermatitis 2007;56:360-1.
    2. 33791. Ozden, M. G., Oztas, P., Oztas, M. O., and Onder, M. Allergic contact dermatitis from Laurus nobilis (laurel) oil. Contact Dermatitis 2001;45(3):178. PubMed
    3. 33864. Cheminat, A., Stampf, J. L., and Benezra, C. Allergic contact dermatitis to laurel (Laurus nobilis L.): isolation and identification of haptens. Arch Dermatol Res 1984;276(3):178-181. PubMed
    4. 104767. Vassileva S, Darlenski R. Bay leaf phytodermatitis. Contact Dermatitis. 2020 Nov 15. PubMed

    Sulfamethoxazole, Trimethoprim

    Listed in the ADVERSE REACTIONS section of the FDA label for Sulfamethoxazole, Trimethoprim. Read the label on DailyMed ›

  • A skin rash Additional detail

    Bay Leaf

    Recorded for Bay Leaf in the same Natural Medicines adverse-effect record shown under An allergic reaction above.

    Sulfamethoxazole, Trimethoprim

    Listed in the ADVERSE REACTIONS section of the FDA label for Sulfamethoxazole, Trimethoprim. Read the label on DailyMed ›

Reported for Bay Leaf but not commonly for Sulfamethoxazole, Trimethoprim: wheezing.

Effects for Sulfamethoxazole, Trimethoprim come from the ADVERSE REACTIONS section of its FDA label; effects for Bay Leaf 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.

Everything else you take

See Every Supplement That Interacts With Sulfamethoxazole, Trimethoprim

This page covers Bay Leaf only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Sulfamethoxazole, Trimethoprim page lists 174 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), Arsenic (major), Beer (major) and Cesium (major).

By severity: 11 major · 139 moderate · 24 minor.

From our pharmacist’s overview on the Sulfamethoxazole, Trimethoprim page

“The supplement I check first with sulfamethoxazole and trimethoprim (Bactrim, Septra) is PABA, because it feeds bacteria the exact compound this antibiotic works by blocking and can cancel the treatment outright. It is one of 11 major-rated entries among 174 supplements and herbs on file here, a count that calls for genuine care.”

Reviewed by 2 · Jul 18, 2026

Open the Sulfamethoxazole, Trimethoprim interaction page

How much people look this up

Where Bay Leaf and Sulfamethoxazole, Trimethoprim 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 Bay Leaf
Top 25%

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

29 days ago today
Medication Sulfamethoxazole, Trimethoprim
Top half

#1,273 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 Bay Leaf reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Bay Leaf and Sulfamethoxazole, Trimethoprim 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 Bay Leaf

What is Bay Leaf?

Bay Leaf
  • Cooking and flavoring
  • Digestive upset
  • Blood sugar support
  • Colds and congestion
  • Joint and muscle discomfort

Bay leaf is a common culinary herb that is safe in the small amounts used in cooking. Some people take it for digestion, blood sugar, or colds, but strong human evidence for these uses is lacking. Talk to your pharmacist or doctor before using concentrated supplements or essential oils.

Laurus nobilis · Lauraceae · Leaves and essential oil · Whole or ground dried leaves, tea, capsules, extracts, essential oil

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

Bay Leaf: dosing

There is no standardized or proven medicinal dose for bay leaf. In cooking, one or two whole leaves are typically added during simmering and then removed before serving.For teas, extracts, and capsules, follow the directions on the product label, since strength varies widely between products.

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

Read the full Bay Leaf monograph & all interactions
Keep checking

Other Drugs & Bay Leaf

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

0Major
335Moderate
0Minor
2,494No known interaction
335 Moderate 2,494 No interaction
Moderate

335 interactions

Showing 60 of 335 moderate interactions — see all 335 on the Bay Leaf page.

No interaction 2,494 drugs checked — show the list

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

Showing the 60 most looked-up of 2,494 medications checked with no known interaction — see the full Bay Leaf list.

See the full Bay Leaf interactions page
See every supplement checked against Sulfamethoxazole, Trimethoprim, ranked by severity
Evidence & sources

Bay Leaf References

The 7 references that drive our Bay Leaf 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. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  2. Cartier LC, Lehrer A, Malo JL. Occupational asthma caused by aromatic herbs. Allergy 1996;51:647-9. DOI
  3. Adisen E, Onder M. Allergic contact dermatitis from Laurus nobilis oil induced by massage. Contact Dermatitis 2007;56:360-1.
  4. Ozden, M. G., Oztas, P., Oztas, M. O., and Onder, M. Allergic contact dermatitis from Laurus nobilis (laurel) oil. Contact Dermatitis 2001;45(3):178. PubMed
  5. Khan, A., Zaman, G., and Anderson, R. A. Bay leaves improve glucose and lipid profile of people with type 2 diabetes. J Clin Biochem.Nutr. 2009;44(1):52-56. PubMed
  6. Cheminat, A., Stampf, J. L., and Benezra, C. Allergic contact dermatitis to laurel (Laurus nobilis L.): isolation and identification of haptens. Arch Dermatol Res 1984;276(3):178-181. PubMed
  7. Vassileva S, Darlenski R. Bay leaf phytodermatitis. Contact Dermatitis. 2020 Nov 15. PubMed

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 Bay Leaf and Sulfamethoxazole, Trimethoprim Together: Common Questions

Is it safe to take Bay Leaf with Sulfamethoxazole, Trimethoprim?
We do not list a known interaction between Bay Leaf and Sulfamethoxazole, Trimethoprim. 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 Bay Leaf and Sulfamethoxazole, Trimethoprim have any of the same side effects?
Yes — our sources link each of them separately to 2 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 Bay Leaf and Sulfamethoxazole, Trimethoprim combination checked?
Interactions in our licensed database are recorded against drug classes. Sulfamethoxazole, Trimethoprim is filed under 9 classifications, and Bay Leaf has documented interactions with 3 drug classes — none of Sulfamethoxazole, Trimethoprim'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 Bay Leaf interact with any other medications?
Yes. Bay Leaf has 335 documented drug interactions in our database — Sulfamethoxazole, Trimethoprim 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 Sulfamethoxazole, Trimethoprim interact with any supplements?
Yes. Sulfamethoxazole, Trimethoprim has documented interactions with 174 supplements in our database — Bay Leaf is not one of them. The Sulfamethoxazole, Trimethoprim 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

Bay Leaf monograph Uses, safety profile, and every drug interaction in one place Sulfamethoxazole, Trimethoprim supplement interactions Every supplement checked against Sulfamethoxazole, Trimethoprim, 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 7 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Sulfamethoxazole, Trimethoprim and Bay Leaf?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.