Drug & supplement interaction

Manna + Reserpine, Trichlormethiazide

Reserpine, Trichlormethiazide brand names: Naquival, Metatensin #2, Metatensin #4.

Moderate Interaction
The bottom line Moderate

Manna has a moderate interaction with Reserpine, Trichlormethiazide. Theoretically, manna might increase the risk of hypokalemia when taken with diuretic drugs.

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

Manna and Reserpine, Trichlormethiazide

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

Moderate

DIURETIC DRUGS

Why this applies to Reserpine, Trichlormethiazide

Reserpine, Trichlormethiazide falls under DIURETIC DRUGS — the group Manna interacts with.

Theoretically, manna might increase the risk of hypokalemia when taken with diuretic drugs.
Manna contains mannitol, which acts as an osmotic laxative. Overuse of manna might compound diuretic-induced potassium loss, increasing the risk of hypokalemia.
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

Your medication is a combo pill: reserpine helps lower blood pressure, and trichlormethiazide is a water pill (thiazide diuretic). One known thing thiazides do is make your body lose potassium through the urine. Manna is a gentle laxative because the mannitol in it pulls water into your gut. If you overdo manna and end up with loose stools, you can lose potassium and fluids that way too, on top of what the water pill is already doing.

This is a theoretical concern based on how these work, not something proven in studies. Low potassium can cause muscle cramps, weakness, tiredness, or an irregular heartbeat. Occasional, normal use of manna is unlikely to be a problem. If you plan to use it regularly, please check with your pharmacist or doctor first, and don't change your blood pressure medicine on your own.

References
  1. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

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

Manna Also Interacts With Other Medications

Manna has 98 moderate known drug interactions in our database — the Reserpine, Trichlormethiazide 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 Manna

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

Everything else you take

See Every Supplement That Interacts With Reserpine, Trichlormethiazide

This page covers Manna only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Reserpine, Trichlormethiazide page lists 228 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 Dolomite (major).

By severity: 10 major · 193 moderate · 25 minor.

From our pharmacist’s overview on the Reserpine, Trichlormethiazide page

“American hellebore is the entry I would flag first on this page. Even small amounts can drive blood pressure down hard, and reserpine with trichlormethiazide (Naquival, Metatensin) is already a two-drug combination built to lower it.”

Reviewed by 2 · Jul 18, 2026

Open the Reserpine, Trichlormethiazide interaction page

One more smart check

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

We hold 27 real supplement products containing Manna, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Manna. Your product may carry other ingredients that interact with Reserpine, Trichlormethiazide too, on top of Manna — 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 Manna and Reserpine, Trichlormethiazide 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 Manna
Top half

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

29 days ago today
Medication Reserpine, Trichlormethiazide
Steady interest

#2,297 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 Manna

What is Manna?

Manna
  • Gentle constipation relief
  • Mild laxative for children and elderly
  • Natural sweetener
  • Occasional bowel softening

Manna is the dried, sweet sap of the flowering ash tree (Fraxinus ornus) and is best known as a gentle, mild laxative because it contains a sugar alcohol called mannitol. It is generally considered mild and is sometimes used for occasional constipation, but high-quality modern studies are limited, so talk with your pharmacist or doctor before using it.

Read the full Manna monograph & all interactions
Keep checking

Other Drugs & Manna

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

0Major
98Moderate
0Minor
2,731No known interaction
Moderate

98 interactions

Showing 60 of 98 moderate interactions — see all 98 on the Manna page.

No interaction 2,731 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 Manna and Reserpine, Trichlormethiazide Together: Common Questions

Can you take Manna with Reserpine, Trichlormethiazide?
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 Manna and Reserpine, Trichlormethiazide 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 Reserpine, Trichlormethiazide and Manna?

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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.