Drug & supplement interaction

Methylsynephrine + Amivantamab-Vmjw

Amivantamab-Vmjw brand name: Rybrevant.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Methylsynephrine and Amivantamab-Vmjw 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. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Methylsynephrine and Amivantamab-Vmjw

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 Amivantamab-Vmjw and Methylsynephrine 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.

Methylsynephrine safety at a glance

Methylsynephrine overall Avoid It is a stimulant drug not approved as a supplement and has been tied to serious cardiovascular events.
Pregnancy Avoid Stimulant with unknown safety; should not be used during pregnancy.
Breastfeeding Avoid No safety data; avoid while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Amivantamab-Vmjw and Methylsynephrine? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
Keep it in perspective

Methylsynephrine Does Interact With Other Medications

Methylsynephrine has 191 moderate known drug interactions in our database — Amivantamab-Vmjw isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Methylsynephrine

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

What to actually watch for

No Interaction Found — But Data Suggests Methylsynephrine and Amivantamab-Vmjw May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do.

  • Vomiting / Nausea Additional detail

    Methylsynephrine

    “In the Netherlands, the supplement dexaprine was removed from the market following reported cases of nausea and vomiting. As little as half a tablet was associated with these adverse effects, which occurred within one hour of ingestion. Dexaprine was found to contain methylsynephrine, synephrine, deterenol, yohimbine, caffeine, theophylline, and possibly beta-methyl-beta-phenylethylamines.”

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

    1 source cited
    1. 99913. Venhuis B, Keizers P, van Riel A, de Kaste D. A cocktail of synthetic stimulants found in a dietary supplement associated with serious adverse events. Drug Test Anal. 2014;6(6):578-81. PubMed

    Amivantamab-Vmjw

    Listed in the ADVERSE REACTIONS section of the FDA label for Amivantamab-Vmjw. Read the label on DailyMed ›

Reported for Methylsynephrine but not commonly for Amivantamab-Vmjw: raised blood pressure, a fast or pounding heartbeat, an irregular heartbeat and chest pain.

Effects for Amivantamab-Vmjw come from the ADVERSE REACTIONS section of its FDA label; effects for Methylsynephrine come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

One more smart check

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

We hold 55 real supplement products containing Methylsynephrine, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Methylsynephrine. Even though Methylsynephrine itself has no known interaction with Amivantamab-Vmjw, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Methylsynephrine and Amivantamab-Vmjw 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 Methylsynephrine
Top 25%

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

29 days ago today
Medication Amivantamab-Vmjw
Top half

#1,025 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 Methylsynephrine reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Methylsynephrine and Amivantamab-Vmjw 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 Methylsynephrine

What is Methylsynephrine?

  • Weight loss and fat burning
  • Boosting energy
  • Athletic and workout performance
  • Appetite control

Methylsynephrine (also called oxilofrine) is a synthetic stimulant sometimes added to weight-loss and pre-workout products, but it is not a legal or approved dietary ingredient in the United States. It has been linked to serious heart and blood pressure problems, and there is no good evidence it is safe or effective for these uses, so it is best avoided.

Synthetic compound (also reported in some Citrus species) · Capsules, tablets, powders (mostly in weight-loss and pre-workout supplements)

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

Methylsynephrine: dosing

There is no established safe or approved dose of methylsynephrine for use as a dietary supplement, and we will not suggest one. It is not a legal supplement ingredient in the United States.Supplement labels may list it under different names (such as oxilofrine or methylsynephrine) and amounts can be inconsistent or unreliable. The safest choice is to avoid products that contain it.

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

Read the full Methylsynephrine monograph & all interactions
Medication

About Amivantamab-vmjw Injection

What Is Amivantamab-vmjw Injection Used For?

Brand name: Rybrevant

Rybrevant (amivantamab-vmjw) is used to treat adults with locally advanced or metastatic non-small cell lung cancer (NSCLC) that carries specific changes (mutations) in the EGFR gene. The exact regimen depends on which mutation is present and whether prior treatment has been received.

Rybrevant is used: in combination with lazertinib as a first-line treatment for NSCLC with EGFR exon 19 deletions or exon 21 L858R mutations; in combination with carboplatin and pemetrexed for those same mutations when the cancer progressed after an EGFR tyrosine kinase inhibitor; in combination with carboplatin and pemetrexed as a first-line treatment for NSCLC with EGFR exon 20 insertion mutations; and as a single agent for NSCLC with exon 20 insertion mutations when the cancer progressed after platinum-based chemotherapy. In every case, patients must first be confirmed to carry the relevant mutation by an FDA-approved test.

See full Amivantamab-vmjw Injection drug information
Keep checking

Other Drugs & Methylsynephrine

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

0Major
191Moderate
0Minor
2,638No known interaction
Moderate

191 interactions

Showing 60 of 191 moderate interactions — see all 191 on the Methylsynephrine page.

No interaction 2,638 drugs checked — show the list
Evidence & sources

Methylsynephrine References

The 3 references that drive our Methylsynephrine 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. Pawar RS, Grundel E. Overview of regulation of dietary supplements in the USA and issues of adulteration with phenethylamines (PEAs). Drug Test Anal 2017;9:500-517. PubMed
  2. Cohen PA, Avula B, Venhuis B, Travis JC, Wang YH, Khan IA. Pharmaceutical doses of the banned stimulant oxilofrine found in dietary supplements sold in the USA. Drug Test Anal. 2017;9(1):135-142. PubMed
  3. Venhuis B, Keizers P, van Riel A, de Kaste D. A cocktail of synthetic stimulants found in a dietary supplement associated with serious adverse events. Drug Test Anal. 2014;6(6):578-81. PubMed

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 Methylsynephrine and Amivantamab-Vmjw Together: Common Questions

Is it safe to take Methylsynephrine with Amivantamab-Vmjw?
We do not list a known interaction between Methylsynephrine and Amivantamab-Vmjw. 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.
Do Methylsynephrine and Amivantamab-Vmjw have any of the same side effects?
Yes — our sources link each of them separately to 2 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Does Methylsynephrine interact with any other medications?
Yes. Methylsynephrine has 191 documented drug interactions in our database — Amivantamab-Vmjw is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.

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

Still Have a Question About Amivantamab-Vmjw and Methylsynephrine?

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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.