Drug & supplement interaction

St. John's Wort + Moexipril

Moexipril brand name: Univasc.

Moderate Interaction
The bottom line Moderate

St. John's Wort has a moderate interaction with Moexipril. Theoretically, St. John's wort might increase the likelihood for photosensitivity reactions when used in combination with photosensitizing drugs.

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

St. John's Wort and Moexipril

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

Moderate

PHOTOSENSITIZING DRUGS

Why this applies to Moexipril

Moexipril falls under PHOTOSENSITIZING DRUGS — the group St. John's Wort interacts with.

Theoretically, St. John's wort might increase the likelihood for photosensitivity reactions when used in combination with photosensitizing drugs.
St. John's wort might increase photosensitivity reactions due to its hypericin content. However, some clinical research shows that very high doses of St. John's wort are needed to produce phototoxicity in humans.
Severity Moderate Likelihood Possible Evidence D

Interaction 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.

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

Here's the thing to know if you're pairing St. John's wort with moexipril: this particular concern isn't about your blood pressure control or how the moexipril works. It's about your skin and sun sensitivity. St. John's wort contains a compound called hypericin that can make your skin more reactive to sunlight, and moexipril is grouped with medicines that can do the same. Together, in theory, you might sunburn faster or develop a rash more easily.

I'll be honest, this is mostly a theoretical worry. Studies suggest you'd need quite high doses of St. John's wort before real sun problems show up. Still, it's smart to use sunscreen and check with your pharmacist or doctor before combining them, since St. John's wort has other serious interactions too.

References
  1. Miller LG. Herbal Medicinals: Selected clinical considerations focusing on known or potential drug-herb interactions. Arch Intern Med 1998;158:2200-11.
  2. Peirce A. The American Pharmaceutical Association Practical Guide to Natural Medicines. New York, NY: William Morrow and Co., 1999.
  3. Schempp CM, Muller K, Winghofer B, et al. Single-dose and steady-state administration of Hypericum perfotatum extract (St. John's wort) does not influence skin sensitivity to UV radiation, visible light, and solar-stimulated radiation. Arch Dermatol 2001;
  4. Bernd A, Ramirez-Bosca A, Kippenberger S, and et al. Phototoxic effects of Hypericum extract in cultures of human keratinocytes compared with those of psoralen. Photochem Photobiol 1999;2(69):218-221.
  5. Pochet S, Lechon AS, Lescrainier C, et al. Herb-anticancer drug interactions in real life based on VigiBase, the WHO global database. Sci Rep 2022;12(1):14178. 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

St. John's Wort Also Interacts With Other Medications

St. John's Wort has 755 major, 387 moderate known drug interactions in our database — the Moexipril one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against St. John's Wort

Covers the 2,830 medications we’ve checked against St. John's Wort. Pick one to open its full report.

From our Q&A

Questions About St. John's Wort or Moexipril

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers St. John's Wort or Moexipril, 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 Moexipril

This page covers St. John's Wort only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Moexipril page lists 177 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), Arsenic (major) and Asarabacca (major).

By severity: 11 major · 143 moderate · 23 minor.

From our pharmacist’s overview on the Moexipril page

“If you take moexipril (Univasc) for high blood pressure, look hard at this list before adding a supplement; 11 of the 177 ingredients on file are rated major. Most, 119 ingredients, affect blood pressure itself, some dropping it further and others working against the drug.”

Reviewed by 2 · Jul 18, 2026

Open the Moexipril interaction page

One more smart check

Taking St. John's Wort as Part of a Dietary Supplement Product? Check It for Interactions

We hold 1,159 real supplement products containing St. John's Wort, each one broken down to its full ingredient list — and combination products often carry several ingredients besides St. John's Wort. Your product may carry other ingredients that interact with Moexipril too, on top of St. John's Wort — 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 St. John's Wort and Moexipril 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 St. John's Wort
Top 25%

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

29 days ago today
Medication Moexipril
Top half

#1,408 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 St. John's Wort

What is St. John's Wort?

St. John's Wort
  • Mild to moderate depression
  • Anxiety and stress
  • Sleep problems
  • Menopausal symptoms
  • Wound healing (topical)

St. John's wort is a well-studied herb most often used for mild to moderate depression, and some research suggests it may help with this. However, it has many serious interactions with prescription medicines and is not safe for everyone, so always talk to your pharmacist or doctor before taking it.

Read the full St. John's Wort monograph & all interactions
Medication

About Moexipril

What Is Moexipril Used For?

Brand name: Univasc

Moexipril Hydrochloride tablets are used to treat high blood pressure (hypertension). They can be used on their own or combined with thiazide diuretics (water pills) when blood pressure is not controlled by moexipril alone.

It's worth knowing that ACE inhibitors, including moexipril, tend to lower blood pressure less effectively in Black patients than in non-Black patients, and Black patients also have a higher risk of a serious swelling reaction called angioedema with ACE inhibitors.

See full Moexipril drug information
Keep checking

Other Drugs & St. John's Wort

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

755Major
387Moderate
0Minor
1,687No known interaction
Major

755 interactions

Showing 60 of 755 major interactions — see all 755 on the St. John's Wort page.

Moderate

387 interactions

Showing 60 of 387 moderate interactions — see all 387 on the St. John's Wort page.

No interaction 1,687 drugs checked — show the list
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

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Pharmacist Counseling Corner

Taking St. John's Wort and Moexipril Together: Common Questions

Can you take St. John's Wort with Moexipril?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the St. John's Wort and Moexipril interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

Still Have a Question About Moexipril and St. John's Wort?

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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.