Drug & supplement interaction

Iboga + Dextromethorphan, Methscopolamine, Phenylephrine

Dextromethorphan, Methscopolamine, Phenylephrine brand name: DA Chewable.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Dextromethorphan, Methscopolamine, Phenylephrine falls into 2 drug categories that Iboga can interact with; the most serious is rated moderate. Theoretically, taking iboga with serotonergic drugs might increase levels of serotonin, resulting in additive effects with serotonergic drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Iboga and Dextromethorphan, Methscopolamine, Phenylephrine

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

Why Are There 2 Interactions?

Iboga interacts with whole categories of medication. Dextromethorphan, Methscopolamine, Phenylephrine falls into 2 of those categories, so it can interact with Iboga in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

SEROTONERGIC DRUGS

1 of 2

Why this applies to Dextromethorphan, Methscopolamine, Phenylephrine

Dextromethorphan, Methscopolamine, Phenylephrine falls under SEROTONERGIC DRUGS — the group Iboga interacts with.

Theoretically, taking iboga with serotonergic drugs might increase levels of serotonin, resulting in additive effects with serotonergic drugs.
Ibogaine, a constituent in iboga, has serotonergic effects. Theoretically, combining serotonergic drugs with iboga might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders. Monitor patients for signs of serotonin syndrome and other serotonergic side effects if using iboga with serotonergic drugs.
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

In this combo product, the piece that matters most here is the dextromethorphan (the cough suppressant). Dextromethorphan can nudge serotonin levels up in the brain, and Iboga's main compound, ibogaine, does the same thing. Stacking two serotonin-raising substances can theoretically add together and, in rare cases, trigger serotonin syndrome, which can show up as agitation, fast heartbeat, sweating, shivering, muscle twitching, or confusion.

I'll be honest: this concern is theoretical, based on how these things work rather than real reported cases. Still, Iboga carries serious heart rhythm risks on its own and isn't something I'd recommend using. The phenylephrine and methscopolamine in this product aren't the serotonin issue. If you're considering anything with Iboga, please run it by your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Glick SD, Maisonneuve IS. Mechanisms of antiaddictive actions of ibogaine. Ann N Y Acad Sci 1998;844:214-26.
  2. Singhal AB, Caviness VS, Begleiter AF, et al. Cerebral vasoconstriction and stroke after use of serotonergic drugs. Neurology 2002;58:130-3. PubMed
  3. Litjens RP, Brunt TM. How toxic is ibogaine? Clin Toxicol (Phila). 2016;54(4):297-302. PubMed
Moderate

ANTICHOLINERGIC DRUGS

2 of 2

Dextromethorphan, Methscopolamine, Phenylephrine also falls under ANTICHOLINERGIC DRUGS.

Theoretically, iboga might decrease the effectiveness of anticholinergic drugs.
In vitro research shows that iboga can inhibit acetylcholinesterase and might increase acetylcholine levels. However, the constituent ibogaine does not appear to have this effect.
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

The piece of your combo product that matters here is the methscopolamine, which is an anticholinergic. It works by blocking the action of acetylcholine, a nerve messenger that helps dry up secretions. The theory on file is that Iboga may raise acetylcholine levels by slowing the enzyme that breaks it down. If that happened, it could partly push back against the methscopolamine, making it work less well. In plain terms, you might notice less of the drying effect you took it for.

I want to be honest about how shaky this is. It comes only from lab studies, and the main compound in Iboga, ibogaine, did not show this effect. Separately, Iboga is illegal in the U.S. and carries real heart rhythm dangers, so I would not use it. Please check with your pharmacist before mixing anything new.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Alper K, Reith ME, Sershen H. Ibogaine and the inhibition of acetylcholinesterase. J Ethnopharmacol. 2012;139(3):879-82. 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

Iboga Also Interacts With Other Medications

Iboga has 1 major, 500 moderate known drug interactions in our database — the Dextromethorphan, Methscopolamine, Phenylephrine one above is among them. If you take anything else, check it against the full list below.

Major 1 Moderate 500 No known interaction 2,329 (incl. Dextromethorphan, Methscopolamine, Phenylephrine)
Taking anything else?

Check Another of Your Medications Against Iboga

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

Everything else you take

See Every Supplement That Interacts With Dextromethorphan, Methscopolamine, Phenylephrine

This page covers Iboga only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dextromethorphan, Methscopolamine, Phenylephrine page lists 220 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Ephedra (major), Grapefruit (major), Henbane (major) and Lithium (major).

By severity: 10 major · 166 moderate · 44 minor.

From our pharmacist’s overview on the Dextromethorphan, Methscopolamine, Phenylephrine page

“Dextromethorphan with methscopolamine and phenylephrine (DA Chewable) packs a cough suppressant, a drying agent, and a decongestant into one tablet, which gives supplements several distinct ways to cause trouble, so I treat this as a list deserving real caution. Grapefruit can drive levels of the drug up by blocking its breakdown, St.”

Reviewed by 2 · Jul 18, 2026

Open the Dextromethorphan, Methscopolamine, Phenylephrine interaction page

How much people look this up

Where Iboga and Dextromethorphan, Methscopolamine, Phenylephrine 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 Iboga
Top half

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

29 days ago today
Medication Dextromethorphan, Methscopolamine, Phenylephrine
Top 25%

#700 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 Iboga

What is Iboga?

Iboga
  • Drug and alcohol addiction
  • Opioid withdrawal
  • Spiritual and ceremonial rituals
  • Fatigue and stimulant effects
  • Mood and emotional issues

Iboga is a Central African shrub whose root bark contains ibogaine, a powerful hallucinogenic compound studied mainly for addiction. It carries serious safety risks, including dangerous heart rhythm changes and deaths, and ibogaine is illegal in the United States and many other countries. We do not recommend its use outside of tightly controlled research settings.

Read the full Iboga monograph & all interactions
Keep checking

Other Drugs & Iboga

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

1Major
500Moderate
0Minor
2,328No known interaction
1 Major 500 Moderate 2,328 No interaction
Major

1 interaction

Moderate

500 interactions

Showing 60 of 500 moderate interactions — see all 500 on the Iboga page.

No interaction 2,328 drugs checked — show the list

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

Showing the 60 most looked-up of 2,328 medications checked with no known interaction — see the full Iboga list.

See the full Iboga interactions page
See every supplement checked against Dextromethorphan, Methscopolamine, Phenylephrine, ranked by severity
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

Keep exploring
Iboga monograph › Uses, safety, and every drug interaction in one place Dextromethorphan, Methscopolamine, Phenylephrine supplement interactions › Every supplement checked against Dextromethorphan, Methscopolamine, Phenylephrine, 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 Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Iboga and Dextromethorphan, Methscopolamine, Phenylephrine Together: Common Questions

Can you take Iboga with Dextromethorphan, Methscopolamine, Phenylephrine?
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.
Why are there 2 interactions listed for Iboga and Dextromethorphan, Methscopolamine, Phenylephrine?
Dextromethorphan, Methscopolamine, Phenylephrine belongs to more than one drug category, and Iboga 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 Iboga and Dextromethorphan, Methscopolamine, Phenylephrine 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 Dextromethorphan, Methscopolamine, Phenylephrine and Iboga?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.