Drug & supplement interaction

Cowhage + Hydrochlorothiazide, Methyldopa

Hydrochlorothiazide, Methyldopa brand names: Aldoril 15, Methazide, Aldoril 25, Aldoril D30.

Major Interaction
Medically reviewed by · Updated September 2026
The bottom line Major

Cowhage has a major interaction with Hydrochlorothiazide, Methyldopa. Theoretically, concomitant use of cowhage and methyldopa might increase the risk of hypotension.

Read the full interaction report
SeverityMajor
LikelihoodProbable
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Cowhage and Hydrochlorothiazide, Methyldopa

Here is the interaction we found between these two, with the evidence behind it.

Major

METHYLDOPA (Aldomet)

Theoretically, concomitant use of cowhage and methyldopa might increase the risk of hypotension.
Cowhage contains levodopa. Use of levodopa with methyldopa might cause additive hypotension. In addition, methyldopa may inhibit peripheral decarboxylation of levodopa and increase levodopa levels in the central nervous system; avoid using.
Severity Major Likelihood Probable Evidence D

Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Your combo pill pairs methyldopa (a blood pressure medicine) with hydrochlorothiazide (a water pill). Cowhage seeds naturally carry L-dopa, the same active compound found in some Parkinson's medicines. On paper, combining the two raises a couple of concerns. Both can lower blood pressure, so stacking them may add up and leave you feeling dizzy, lightheaded, or faint, especially when you stand up quickly.

There's also a twist: methyldopa can let more L-dopa reach your brain, which can throw off how either one works. To be clear, this is a theoretical caution based on how these compounds behave, not proven in studies. Still, since it's flagged as major, please don't start cowhage without checking with your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. HP-200 in Parkinson's Disease study group. An alternative medicine treatment for Parkinson's disease: Results of a multicenter clinical trial. J Alt Comp Med 1995;1:249-55. DOI
  3. Vadivel V, Janardhanan K. Nutritional and anti-nutritional composition of velvet bean: an under-utilized food legume in south India. Int J Food Sci Nutr 2000;51:279-87. PubMed
  4. Prakash, D., Niranjan, A., and Tewari, S. K. Some nutritional properties of the seeds of three Mucuna species. Int.J.Food Sci.Nutr. 2001;52(1):79-82.
  5. Vadivel, V. and Janardhanan, K. Nutritional and antinutritional characteristics of seven South Indian wild legumes. Plant Foods Hum.Nutr 2005;60(2):69-75. PubMed
  6. Creapure (Creatine Monohydrate). Toxicological Datasheet. Degussa BioActives. Available at: https://www.fda.gov/ohrms/DOCKETS/.../95s-0316-rpt0154-54-Ref-50-vol112.pdf.
  7. Pulikkalpura H, Kurup R, Mathew PJ, Baby S. Levodopa in Mucuna pruriens and its degradation. Sci Rep 2015;5:11078. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Cowhage Also Interacts With Other Medications

Cowhage has 16 major, 176 moderate known drug interactions in our database — the Hydrochlorothiazide, Methyldopa one above is one of them. If you take anything else, check it against the full list below.

Major 16 Moderate 176 No known interaction 2,638 (incl. Hydrochlorothiazide, Methyldopa)
Taking anything else?

Check Another of Your Medications Against Cowhage

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

Everything else you take

See Every Supplement That Interacts With Hydrochlorothiazide, Methyldopa

This page covers Cowhage only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Hydrochlorothiazide, Methyldopa page lists 261 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 13 major · 223 moderate · 25 minor.

From our pharmacist’s overview on the Hydrochlorothiazide, Methyldopa page

“If you take hydrochlorothiazide with methyldopa (Aldoril, Methazide), this list deserves real attention, and the 13 major-rated entries are where to start. Most of the 261 ingredients either push blood pressure lower than intended or add to the diuretic effect, which can drain potassium.”

Reviewed by 2 · Jul 18, 2026

Open the Hydrochlorothiazide, Methyldopa interaction page

One more smart check

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

We hold 1,218 real supplement products containing Cowhage, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Cowhage. Your product may carry other ingredients that interact with Hydrochlorothiazide, Methyldopa too, on top of Cowhage — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Cowhage and Hydrochlorothiazide, Methyldopa 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 Cowhage
Top 10%

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

29 days ago today
Medication Hydrochlorothiazide, Methyldopa
Top 25%

#573 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.

Supplement

About Cowhage

What is Cowhage?

  • Parkinson's disease symptoms
  • Male fertility and libido
  • Mood and stress support
  • Traditional aphrodisiac
  • General energy and vitality

Cowhage (Mucuna pruriens) is a tropical legume best known as a natural source of L-dopa, the compound the body turns into dopamine. It is most studied for Parkinson's disease symptoms and male fertility, but evidence is still limited and the L-dopa content makes it potentially powerful and risky—talk to your doctor or pharmacist before using it.

Read the full Cowhage monograph & all interactions
Keep checking

Other Drugs & Cowhage

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

16Major
176Moderate
0Minor
2,637No known interaction
16 Major 176 Moderate 2,637 No interaction
Major

16 interactions

Moderate

176 interactions

Showing 60 of 176 moderate interactions — see all 176 on the Cowhage page.

No interaction 2,637 drugs checked — show the list

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

Showing the 60 most looked-up of 2,637 medications checked with no known interaction — see the full Cowhage list.

See the full Cowhage interactions page
See every supplement checked against Hydrochlorothiazide, Methyldopa, ranked by severity
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Keep exploring
Cowhage monograph › Uses, safety, and every drug interaction in one place Hydrochlorothiazide, Methyldopa supplement interactions › Every supplement checked against Hydrochlorothiazide, Methyldopa, 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 Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Cowhage and Hydrochlorothiazide, Methyldopa Together: Common Questions

Can you take Cowhage with Hydrochlorothiazide, Methyldopa?
This is rated a major interaction, so the combination is best avoided unless your doctor or pharmacist has specifically told you otherwise. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Cowhage and Hydrochlorothiazide, Methyldopa interaction?
We rate it Major. This is a clinically significant combination that is generally best avoided, or used only under the direct supervision of your physician or pharmacist.

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

Still Have a Question About Hydrochlorothiazide, Methyldopa and Cowhage?

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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.