Drug & supplement interaction

Swamp Milkweed + Mavacamten

Mavacamten brand name: Camzyos.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 13, 2026
The bottom line No known interaction

We found no known interaction between Swamp Milkweed and Mavacamten in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first.

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Interaction report

Swamp Milkweed and Mavacamten

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Mavacamten and Swamp Milkweed in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Swamp Milkweed safety at a glance

Swamp Milkweed overall Use caution The plant contains toxic sap and cardiac glycoside-like compounds; it is not a well-studied or clearly safe supplement.
Pregnancy Likely Unsafe When used orally due to presence of cardioactive steroids; avoid using. Read the full pregnancy detail
Breastfeeding Likely Unsafe When used orally due to presence of cardioactive steroids; avoid using. Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Mavacamten and Swamp Milkweed? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Mavacamten

Interactions in our licensed database are recorded against drug classes, not just single drug names. Mavacamten is filed under 3 classifications — cytochrome p450 2c19 (cyp2c19) substrates, cytochrome p450 3a4 (cyp3a4) substrates, oral drugs. Swamp Milkweed has documented interactions with 7 drug classes — the most serious being digoxin (lanoxin) (major), quinine (major) and corticosteroids (moderate) — and none of Mavacamten’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Swamp Milkweed Does Interact With Other Medications

Swamp Milkweed has 3 major, 153 moderate known drug interactions in our database — Mavacamten isn’t one of them. If you take anything else, check it against the full list below.

Major 3 Moderate 153 No known interaction 2,674 (incl. Mavacamten)
Taking anything else?

Check Another of Your Medications Against Swamp Milkweed

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

What to actually watch for

What Swamp Milkweed Itself Has Been Linked To

This is not an interaction — nothing below involves Mavacamten. It is the side-effect record for Swamp Milkweed on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Swamp Milkweed, this list is the first place to look. One entry is worth acting on rather than waiting out — marked below.

  • An irregular heartbeat Worth acting on Additional detail

    “Orally, swamp milkweed contains cardiac glycosides, which can cause serious adverse effects.

    Serious Adverse Effects (Rare):

    Orally: Swamp milkweed contains toxic cardiac glycosides that may cause cardiac arrhythmia and death.”

    Swamp Milkweed · Natural Medicines adverse-effect record, reported in arrhythmia.

    “Orally, the cardiac glycosides in swamp milkweed may cause cardiac arrhythmias (18).”

    Swamp Milkweed · Natural Medicines adverse-effect record, reported in arrhythmia.

    1 source cited
    1. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  • Vomiting Additional detail

    “Orally, large amounts of swamp milkweed can cause vomiting (18).”

    Swamp Milkweed · Natural Medicines adverse-effect record, reported in nausea and vomiting.

    1 source cited
    1. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  • Headache Additional detail

    “Orally, the cardiac glycosides in swamp milkweed may cause headache and stupor (18). Visual color disturbances may also occur (18).”

    Swamp Milkweed · Natural Medicines adverse-effect record, reported in cluster headache.

    1 source cited
    1. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.

Everything above comes from the Natural Medicines adverse-effect record for Swamp Milkweed — expand a row for the licensed statement it rests on. We read the ADVERSE REACTIONS section of Mavacamten’s FDA label too, and the two lists don’t meaningfully overlap — which is why no Mavacamten column appears here.

Special populations

Swamp Milkweed in Pregnancy & Breastfeeding

Pregnancy And Lactation Likely Unsafe

When used orally due to presence of cardioactive steroids; avoid using.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

Everything else you take

See Every Supplement That Interacts With Mavacamten

This page covers Swamp Milkweed only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Mavacamten page lists 143 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate) and Adrafinil (moderate).

By severity: 3 major · 100 moderate · 40 minor.

From our pharmacist’s overview on the Mavacamten page

“Grapefruit is the first thing I would set aside for anyone taking mavacamten (Camzyos), the medicine for obstructive hypertrophic cardiomyopathy. It blocks CYP3A4, the liver enzyme that clears mavacamten, and too much of this drug can weaken the heart's pumping strength, the very problem careful dosing exists to prevent.”

Reviewed by 2 · Jul 18, 2026

Open the Mavacamten interaction page

How much people look this up

Where Swamp Milkweed and Mavacamten 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 Swamp Milkweed
Steady interest

#1,185 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Mavacamten
Top 25%

#643 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Swamp Milkweed reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Swamp Milkweed and Mavacamten records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Swamp Milkweed

What is Swamp Milkweed?

  • Traditional digestive remedy
  • Diuretic (increasing urine)
  • Cough and respiratory complaints
  • Worm or parasite remedy (folk use)
  • Pollinator/garden plant rather than medicine

Swamp Milkweed is a native North American wetland plant best known today as a butterfly and pollinator garden plant, not a proven medicine. It contains toxic milky sap with cardiac glycoside-like compounds, and there is very little reliable human research to support any health use. Because of its potential toxicity, it should not be used as a supplement without professional guidance.

Asclepias incarnata · Apocynaceae · Root, and historically other parts of the plant · Dried root, tinctures, and traditional decoctions (rarely sold as a commercial supplement)

An interaction check asks whether these two react with each other — it does not ask whether Swamp Milkweed is a good idea for someone in your situation. Here is what our Swamp Milkweed record says about it on its own.

Swamp Milkweed: dosing

There is no established safe or standardized dose for Swamp Milkweed. It is not a mainstream supplement, and reliable products with verified content are not generally available.Because of the plant's toxicity and the lack of research, we cannot recommend any specific amount. For most people, the safest approach is to enjoy Swamp Milkweed as a garden plant rather than to consume it.

From our Swamp Milkweed monograph — the full record covers uses, side effects and every documented interaction.

Read the full Swamp Milkweed monograph & all interactions
Medication

About Mavacamten

What Is Mavacamten Used For?

Brand name: Camzyos

Camzyos (mavacamten) is approved for adults with symptomatic obstructive hypertrophic cardiomyopathy (HCM) — specifically those with New York Heart Association (NYHA) class II or III symptoms, meaning the condition noticeably limits their daily activity. It is used to improve exercise capacity and relieve symptoms like shortness of breath and chest discomfort caused by the obstruction.

See full Mavacamten drug information
Keep checking

Other Drugs & Swamp Milkweed

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

3Major
153Moderate
0Minor
2,673No known interaction
3 Major 153 Moderate 2,673 No interaction
Major

3 interactions

Moderate

153 interactions

Showing 60 of 153 moderate interactions — see all 153 on the Swamp Milkweed page.

No interaction 2,673 drugs checked — show the list

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

Showing the 60 most looked-up of 2,673 medications checked with no known interaction — see the full Swamp Milkweed list.

See the full Swamp Milkweed interactions page
See every supplement checked against Mavacamten, ranked by severity
Evidence & sources

Swamp Milkweed References

The 3 references that drive our Swamp Milkweed monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
  2. Ellenhorn MJ, et al. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins, 1997.
  3. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Swamp Milkweed and Mavacamten Together: Common Questions

Is it safe to take Swamp Milkweed with Mavacamten?
We do not list a known interaction between Swamp Milkweed and Mavacamten. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
How was the Swamp Milkweed and Mavacamten combination checked?
Interactions in our licensed database are recorded against drug classes. Mavacamten is filed under 3 classifications, and Swamp Milkweed has documented interactions with 7 drug classes — none of Mavacamten's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Swamp Milkweed interact with any other medications?
Yes. Swamp Milkweed has 156 documented drug interactions in our database — Mavacamten is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Mavacamten interact with any supplements?
Yes. Mavacamten has documented interactions with 143 supplements in our database — Swamp Milkweed is not one of them. The Mavacamten interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Swamp Milkweed monograph Uses, safety profile, and every drug interaction in one place Mavacamten drug information The full plain-English guide to this medication Mavacamten supplement interactions Every supplement checked against Mavacamten, 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 References The 3 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Mavacamten and Swamp Milkweed?

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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.