Drug & supplement interaction

Hemp + Hydrochlorothiazide, Methyldopa

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

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

Hemp has a minor interaction with Hydrochlorothiazide, Methyldopa. Theoretically, hemp seed protein may have additive effects with antihypertensive drugs.

Read the full interaction report
SeverityMinor
LikelihoodUnlikely
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Hemp and Hydrochlorothiazide, Methyldopa

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

Minor

ANTIHYPERTENSIVE DRUGS

Why this applies to Hydrochlorothiazide, Methyldopa

Hydrochlorothiazide, Methyldopa falls under ANTIHYPERTENSIVE DRUGS — the group Hemp interacts with.

Theoretically, hemp seed protein may have additive effects with antihypertensive drugs.
In a hypertensive animal model, hemp seed protein hydrolysate reduced systolic blood pressure by a mechanism possibly involving the inhibition of renin and angiotensin converting enzyme (ACE) activities. However, there was no effect of hemp seed protein on blood pressure in normotensive animals. Furthermore, hempseed oil consumption does not seem to reduce blood pressure in humans.
Severity Minor Likelihood Unlikely Evidence D

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

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

Here's the simple version: this combo pill pairs a water pill (hydrochlorothiazide) with methyldopa, and both work to bring your blood pressure down. The thought is that hemp seed protein might nudge blood pressure a little lower too, possibly by acting somewhat like an ACE inhibitor. So in theory, stacking them could add up and drop your pressure a bit more than expected.

In real life, this is very unlikely to cause a problem. The evidence comes only from animal studies, and in those, hemp protein didn't lower pressure in animals with normal blood pressure. Hemp oil hasn't lowered blood pressure in people at all. Eating hemp seeds as food is no concern. If you start a concentrated hemp protein supplement and notice dizziness, lightheadedness, or feeling faint when standing, check in with your pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Girgih AT, Alashi A, He R, Malomo S, Aluko RE. Preventive and treatment effects of a hemp seed (Cannabis sativa L.) meal protein hydrolysate against high blood pressure in spontaneously hypertensive rats. Eur J Nutr. 2014;53(5):1237-46. PubMed
  2. Del Bo' C, Deon V, Abello F, et al. Eight-week hempseed oil intervention improves the fatty acid composition of erythrocyte phospholipids and the omega-3 index, but does not affect the lipid profile in children and adolescents with primary hyperlipidemia. 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

Hemp Also Interacts With Other Medications

Hemp has 41 moderate, 896 minor 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.

Moderate 41 Minor 896 No known interaction 1,893 (incl. Hydrochlorothiazide, Methyldopa)
Taking anything else?

Check Another of Your Medications Against Hemp

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

Everything else you take

See Every Supplement That Interacts With Hydrochlorothiazide, Methyldopa

This page covers Hemp 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 Hemp as Part of a Dietary Supplement Product? Check It for Interactions

We hold 720 real supplement products containing Hemp, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Hemp. Your product may carry other ingredients that interact with Hydrochlorothiazide, Methyldopa too, on top of Hemp — 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 Hemp 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 Hemp
Top 25%

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

29 days ago today
Medication Hydrochlorothiazide, Methyldopa
Top 25%

#392 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 Hemp

What is Hemp?

Hemp
  • Plant-based protein source
  • Heart health support
  • Skin and hair health
  • Reducing inflammation
  • General nutrition (omega fatty acids)

Hemp seeds and hemp seed oil are nutritious foods rich in protein, fiber, and healthy omega-3 and omega-6 fatty acids, and they are generally safe for most people as part of the diet. While the nutrition is real, strong human evidence that hemp supplements treat specific medical conditions is limited. Talk with your pharmacist or doctor before using hemp products for a health concern, especially if you are pregnant or breastfeeding.

Read the full Hemp monograph & all interactions
Keep checking

Other Drugs & Hemp

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

0Major
41Moderate
896Minor
1,892No known interaction
41 Moderate 896 Minor 1,892 No interaction
Moderate

41 interactions

Minor

896 interactions

Showing 60 of 896 minor interactions — see all 896 on the Hemp page.

No interaction 1,892 drugs checked — show the list

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

Showing the 60 most looked-up of 1,892 medications checked with no known interaction — see the full Hemp list.

See the full Hemp 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
Hemp 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 Hemp and Hydrochlorothiazide, Methyldopa Together: Common Questions

Can you take Hemp with Hydrochlorothiazide, Methyldopa?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Hemp and Hydrochlorothiazide, Methyldopa interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

Still Have a Question About Hydrochlorothiazide, Methyldopa and Hemp?

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.