Drug & supplement interaction

Bacopa + Dexchlorpheniramine

Dexchlorpheniramine brand names: Polaramine, Polaramine Repetabs.

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

Dexchlorpheniramine falls into 2 drug categories that Bacopa can interact with; the most serious is rated moderate. Theoretically, bacopa might increase the levels and adverse effects of CYP3A4 substrates.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Bacopa and Dexchlorpheniramine

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

Why Are There 2 Interactions?

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

Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

1 of 2

Why this applies to Dexchlorpheniramine

Dexchlorpheniramine falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES — the group Bacopa interacts with.

Theoretically, bacopa might increase the levels and adverse effects of CYP3A4 substrates.
Research on the effects of bacopa extracts on CYP3A4 enzymes is conflicting. Some in vitro evidence suggests that bacopa extract can moderately and competitively inhibit CYP3A4, while other in vitro evidence suggests that any effect is unlikely to be clinically significant.
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

Here's the gist with bacopa and your dexchlorpheniramine. Your body uses a liver enzyme called CYP3A4 to help break this antihistamine down. In lab dish studies, bacopa might slow that enzyme a little. If it did, dexchlorpheniramine could clear out more slowly and build up, which can mean stronger antihistamine effects like extra drowsiness, dry mouth, blurry vision, or feeling foggy.

The honest part: this is only a theoretical concern based on test-tube and animal data, and even those studies disagree. For most people it's unlikely to cause real trouble. Still, if you notice unusual sleepiness or dryness, mention it to your pharmacist or doctor before changing anything.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Kar A, Pandit S, Mukherjee K, Bahadur S, Mukherjee PK. Safety assessment of selected medicinal food plants used in Ayurveda through CYP450 enzyme inhibition study. J Sci Food Agric 2017;97(1):333-40. doi: 10.1002/jsfa.7739. PubMed
  2. Ramasamy S, Kiew LV, Chung LY. Inhibition of human cytochrome P450 enzymes by Bacopa monnieri standardized extract and constituents. Molecules 2014;19(2):2588-601. PubMed
Moderate

ANTICHOLINERGIC DRUGS

2 of 2

Dexchlorpheniramine also falls under ANTICHOLINERGIC DRUGS.

Theoretically, concurrent use might decrease the effectiveness of both agents.
Bacopa seems to inhibit acetylcholinesterase and might increase acetylcholine levels, which could counteract the effects of anticholinergic drugs. Similarly, anticholinergic drugs might counteract the cholinergic effects of bacopa.
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

Here's the simple version. Dexchlorpheniramine works by blocking histamine, and like most older antihistamines it also has anticholinergic activity, meaning it dials down a brain and body messenger called acetylcholine. Bacopa is thought to push acetylcholine levels in the opposite direction. So in theory, the two could partly cancel each other out. Bacopa might make your Polaramine work a little less well at calming your sneezing, runny nose, and itchy eyes, and the antihistamine might blunt whatever memory benefit you're hoping to get from bacopa.

I want to be honest about the strength here: this is a theoretical concern based on how each one behaves, not something proven in real patients. It's worth mentioning to your pharmacist or doctor, but it's not a reason to panic.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Morgan A, Stevens J. Does Bacopa monnieri improve memory performance in older persons? Results of a randomized, placebo-controlled, double-blind trial. J Altern Complement Med 2010;16:753-9.

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

Bacopa Also Interacts With Other Medications

Bacopa has 916 moderate, 13 minor known drug interactions in our database — the Dexchlorpheniramine one above is among them. If you take anything else, check it against the full list below.

Moderate 916 Minor 13 No known interaction 1,901 (incl. Dexchlorpheniramine)
Taking anything else?

Check Another of Your Medications Against Bacopa

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

From our Q&A

Questions About Bacopa or Dexchlorpheniramine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Bacopa or Dexchlorpheniramine, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Dexchlorpheniramine

This page covers Bacopa only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dexchlorpheniramine page lists 198 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 6 major · 149 moderate · 43 minor.

From our pharmacist’s overview on the Dexchlorpheniramine page

“An allergy antihistamine like dexchlorpheniramine (Polaramine) sounds mild, but its interaction list warrants genuine care, and six of the 198 entries carry a major rating. The biggest cluster, 121 ingredients, can raise or lower the drug's blood levels through the liver enzyme that breaks it down.”

Reviewed by 2 · Jul 18, 2026

Open the Dexchlorpheniramine interaction page

One more smart check

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

We hold 1,420 real supplement products containing Bacopa, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Bacopa. Your product may carry other ingredients that interact with Dexchlorpheniramine too, on top of Bacopa — 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 Bacopa and Dexchlorpheniramine 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 Bacopa
Top 10%

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

29 days ago today
Medication Dexchlorpheniramine
Top half

#918 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 Bacopa

What is Bacopa?

Bacopa
  • Memory and cognitive support
  • Anxiety and stress
  • ADHD symptoms
  • Age-related memory decline
  • General brain health

Bacopa is an Ayurvedic herb most often used for memory and thinking. Some small studies suggest it may modestly help memory when taken regularly for several weeks, but the evidence is limited and quality varies. It is generally well tolerated but can cause stomach upset, and it should be avoided in pregnancy and breastfeeding due to a lack of safety data.

Read the full Bacopa monograph & all interactions
Medication

About Chlorpheniramine

What Is Chlorpheniramine Used For?

Brand names: Polaramine, Polaramine Repetabs

Chlorpheniramine is used to temporarily relieve common allergy symptoms caused by hay fever (allergic rhinitis) or other upper respiratory allergies. These include runny nose, sneezing, itchy or watery eyes, and itching of the nose or throat.

These uses are supported across multiple products — including tablets (such as Aller-chlor, Allergy, Allergy Relief, Allergy Time, Anti Allergy, and Chlorpheniramine Maleate), extended-release tablets (Allergy Relief and Chlorphen-12), the oral solution Ed Chlorped Jr, and the inhalers ClorRelief and ClorRelief KIDs.

See full Chlorpheniramine drug information
Keep checking

Other Drugs & Bacopa

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

0Major
916Moderate
13Minor
1,900No known interaction
916 Moderate 13 Minor 1,900 No interaction
Moderate

916 interactions

Showing 60 of 916 moderate interactions — see all 916 on the Bacopa page.

Minor

13 interactions

No interaction 1,900 drugs checked — show the list

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

Showing the 60 most looked-up of 1,900 medications checked with no known interaction — see the full Bacopa list.

See the full Bacopa interactions page
See every supplement checked against Dexchlorpheniramine, 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
Bacopa monograph › Uses, safety, and every drug interaction in one place Dexchlorpheniramine supplement interactions › Every supplement checked against Dexchlorpheniramine, ranked by severity Chlorpheniramine drug information › The full plain-English guide to this medication 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 Bacopa and Dexchlorpheniramine Together: Common Questions

Can you take Bacopa with Dexchlorpheniramine?
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 Bacopa and Dexchlorpheniramine?
Dexchlorpheniramine belongs to more than one drug category, and Bacopa 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 Bacopa and Dexchlorpheniramine 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 Dexchlorpheniramine and Bacopa?

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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.