Drug & supplement interaction

Lemon Balm + Diphenhydramine, Pseudoephedrine

Diphenhydramine, Pseudoephedrine brand name: Actifed Allergy.

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

Lemon Balm has a moderate interaction with Diphenhydramine, Pseudoephedrine. Theoretically, concomitant use of lemon balm might have additive effects with CNS depressant drugs.

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

Lemon Balm and Diphenhydramine, Pseudoephedrine

Here is the interaction we found between these two, with the evidence behind it.

Moderate

CNS DEPRESSANTS

Why this applies to Diphenhydramine, Pseudoephedrine

Diphenhydramine, Pseudoephedrine falls under CNS DEPRESSANTS — the group Lemon Balm interacts with.

Theoretically, concomitant use of lemon balm might have additive effects with CNS depressant drugs.
Lemon balm seems to have CNS depressant activity in animals and in humans.
Severity Moderate Likelihood Possible Evidence B

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

This combo product, Actifed Allergy, pairs two ingredients. The diphenhydramine half is a sedating antihistamine, so it already makes a lot of people feel drowsy, foggy, or sluggish. Lemon balm has its own mild calming, sleepy effect, so taking the two together could stack up and leave you more tired, lightheaded, or slow to react than you expect. The pseudoephedrine half is a stimulant decongestant, so it may partly push the other way, but it doesn't reliably cancel out that extra drowsiness.

To be fair, this is mostly a theoretical concern based on small studies, so it's not a hard no. Just go easy, skip driving until you know how you feel, and check with your pharmacist if you take both often.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Kennedy DO, Scholey AB, Tildesley NT, et al. Modulation of mood and cognitive performance following acute administration of Melissa officinalis (lemon balm). Pharmacol Biochem Behav 2002;72:953-64. PubMed
  2. Soulimani R, Fleurentin J, Mortier F, et al. Neurotropic action of the hydroalcoholic extract of Melissa officinalis in the mouse. Planta Med. 1991 Apr;57:105-9.

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

Lemon Balm Also Interacts With Other Medications

Lemon Balm has 263 moderate known drug interactions in our database — the Diphenhydramine, Pseudoephedrine one above is one of them. If you take anything else, check it against the full list below.

Moderate 263 No known interaction 2,567 (incl. Diphenhydramine, Pseudoephedrine)
Taking anything else?

Check Another of Your Medications Against Lemon Balm

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

From our Q&A

Questions About Lemon Balm or Diphenhydramine, Pseudoephedrine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Lemon Balm or Diphenhydramine, Pseudoephedrine, 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 Diphenhydramine, Pseudoephedrine

This page covers Lemon Balm only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Diphenhydramine, Pseudoephedrine page lists 185 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), Beer (major), Ephedra (major) and Gamma-hydroxybutyrate (ghb) (major).

By severity: 13 major · 150 moderate · 22 minor.

From our pharmacist’s overview on the Diphenhydramine, Pseudoephedrine page

“This medicine pulls in two directions at once, which is exactly why the supplement list for diphenhydramine and pseudoephedrine (Actifed Allergy) is not one to skim. The antihistamine half is sedating, so anything else that slows the brain deepens drowsiness; beer, wine, and kava all carry major ratings, with alcohol the best documented.”

Reviewed by 2 · Jul 18, 2026

Open the Diphenhydramine, Pseudoephedrine interaction page

One more smart check

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

We hold 2,076 real supplement products containing Lemon Balm, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Lemon Balm. Your product may carry other ingredients that interact with Diphenhydramine, Pseudoephedrine too, on top of Lemon Balm — 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 Lemon Balm and Diphenhydramine, Pseudoephedrine 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 Lemon Balm
Top 10%

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

29 days ago today
Medication Diphenhydramine, Pseudoephedrine
Steady interest

#1,515 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 Lemon Balm

What is Lemon Balm?

Lemon Balm
  • Anxiety and stress
  • Sleep problems
  • Digestive upset
  • Cold sores
  • Restlessness or nervousness

Lemon balm is a gentle, lemon-scented mint-family herb traditionally used to ease stress, support sleep, and calm digestion, and topically for cold sores. Early studies are promising but generally small, so the evidence is limited. It is usually well tolerated for most adults, but pregnant or breastfeeding people should check with a doctor or pharmacist first.

Read the full Lemon Balm monograph & all interactions
Keep checking

Other Drugs & Lemon Balm

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

0Major
263Moderate
0Minor
2,566No known interaction
263 Moderate 2,566 No interaction
Moderate

263 interactions

Showing 60 of 263 moderate interactions — see all 263 on the Lemon Balm page.

No interaction 2,566 drugs checked — show the list

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

Showing the 60 most looked-up of 2,566 medications checked with no known interaction — see the full Lemon Balm list.

See the full Lemon Balm interactions page
See every supplement checked against Diphenhydramine, Pseudoephedrine, 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
Lemon Balm monograph › Uses, safety, and every drug interaction in one place Diphenhydramine, Pseudoephedrine supplement interactions › Every supplement checked against Diphenhydramine, Pseudoephedrine, 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 Lemon Balm and Diphenhydramine, Pseudoephedrine Together: Common Questions

Can you take Lemon Balm with Diphenhydramine, Pseudoephedrine?
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.
How serious is the Lemon Balm and Diphenhydramine, Pseudoephedrine 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 Diphenhydramine, Pseudoephedrine and Lemon Balm?

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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.