Drug & supplement interaction

American Mistletoe + Hydralazine, Reserpine

Hydralazine, Reserpine brand names: Serpasil-Apresoline1, Serpasil-Apresoline2.

Major Interaction
The bottom line Major

Hydralazine, Reserpine falls into 2 drug categories that American Mistletoe can interact with; the most serious is rated major. American mistletoe contains phoratoxin, a compound toxic to humans that induces smooth muscle contraction and vasoconstriction, potentially increasing blood pressure and heart rate.

Read the full interaction report
SeverityMajor
LikelihoodProbable
Interactions2
EvidenceC
What do Severity, Likelihood & Evidence mean?
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Interaction report

American Mistletoe and Hydralazine, Reserpine

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

American Mistletoe interacts with whole categories of medication. Hydralazine, Reserpine falls into 2 of those categories, so it can interact with American Mistletoe in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Major).

Major

Antihypertensive Drugs

1 of 2

Why this applies to Hydralazine, Reserpine

Hydralazine, Reserpine falls under Antihypertensive Drugs — the group American Mistletoe interacts with.

American mistletoe contains phoratoxin, a compound toxic to humans that induces smooth muscle contraction and vasoconstriction, potentially increasing blood pressure and heart rate. Case reports of cardiotoxicity have been documented with American mistletoe, and it should not be used with antihypertensive drugs or by individuals with cardiac conditions. American mistletoe is uncommon in dietary supplements, and formulations containing it are generally homeopathic. European mistletoe, which lacks phoratoxin, is more commonly used.
Severity Major Likelihood Probable Evidence C

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

This combination pill pairs hydralazine and reserpine to lower your blood pressure. American mistletoe works against that goal. It contains a toxin called phoratoxin that can tighten blood vessels and stir up the heart, which tends to push blood pressure and heart rate up. So you have two products fighting each other, and the mistletoe may blunt the benefit you get from your medicine or make your numbers harder to control.

There are real case reports of heart trouble linked to American mistletoe, so this isn't just a theory. The good news is true American mistletoe is rare in supplements. Still, please don't take it while you're on this blood pressure combo. If you're curious about a product, run it by your pharmacist or doctor first.

Major

Vasodilators

2 of 2

Hydralazine, Reserpine also falls under Vasodilators.

American mistletoe contains phoratoxin, a compound toxic to humans that induces smooth muscle contraction and vasoconstriction, potentially increasing blood pressure and heart rate. Taking dietary supplements containing American mistletoe may counteract the effects of vasodilator drugs, such as hydralazine. It is important to note that American mistletoe is uncommon in dietary supplements. More commonly, European mistletoe is used as it does not contain phoratoxin.
Severity Major Likelihood Probable Evidence C

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

Here's the gist for this combo. Your Serpasil-Apresoline pairs hydralazine and reserpine to relax your blood vessels and bring your blood pressure down. American mistletoe works in the opposite direction. It contains a toxin called phoratoxin that can tighten blood vessels and nudge blood pressure and heart rate upward. So taking it could blunt the very effect your medicine is trying to achieve, which might mean your blood pressure creeps back up.

The honest caveat: this is graded on weaker evidence, and true American mistletoe is rarely found in supplements (European mistletoe, which lacks phoratoxin, is far more common). Even so, this plant is toxic and not recommended. Before adding any mistletoe product, please check with your pharmacist or doctor first.

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

American Mistletoe Also Interacts With Other Medications

American Mistletoe has 189 major, known drug interactions in our database — the Hydralazine, Reserpine one above is among them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against American Mistletoe

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

Everything else you take

See Every Supplement That Interacts With Hydralazine, Reserpine

This page covers American Mistletoe only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Hydralazine, Reserpine page lists 138 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), Tyramine (major), Adrafinil (moderate) and Agmatine (moderate).

By severity: 4 major · 113 moderate · 21 minor.

Open the Hydralazine, Reserpine interaction page

How much people look this up

Where American Mistletoe and Hydralazine, Reserpine 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 American Mistletoe
Steady interest

#1,281 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Hydralazine, Reserpine
Top half

#1,314 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 American Mistletoe

What is American Mistletoe?

American Mistletoe
  • Traditional folk remedies
  • Digestive complaints
  • Decorative holiday plant

American mistletoe is a parasitic plant that is best known as a holiday decoration, not a proven medicine. It contains toxins that can harm the heart, gut, and blood vessels, and it has little reliable evidence to support any health use. We do not recommend taking it, and all parts should be kept away from children and pets.

Read the full American Mistletoe monograph & all interactions
Keep checking

Other Drugs & American Mistletoe

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

189Major
0Moderate
0Minor
2,640No known interaction
Major

189 interactions

Showing 60 of 189 major interactions — see all 189 on the American Mistletoe page.

No interaction 2,640 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 American Mistletoe and Hydralazine, Reserpine Together: Common Questions

Can you take American Mistletoe with Hydralazine, Reserpine?
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.
Why are there 2 interactions listed for American Mistletoe and Hydralazine, Reserpine?
Hydralazine, Reserpine belongs to more than one drug category, and American Mistletoe interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the American Mistletoe and Hydralazine, Reserpine 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

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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.