Drug & supplement interaction

Datura Wrightii + Diphenhydramine, Pseudoephedrine

Diphenhydramine, Pseudoephedrine brand name: Actifed Allergy.

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

Datura Wrightii has a moderate interaction with Diphenhydramine, Pseudoephedrine. Datura wrightii contains atropine and scopolamine, as well as other tropane alkaloids with anticholinergic activity.

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

Datura Wrightii and Diphenhydramine, Pseudoephedrine

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

Moderate

ANTICHOLINERGIC DRUGS

Why this applies to Diphenhydramine, Pseudoephedrine

Diphenhydramine, Pseudoephedrine falls under ANTICHOLINERGIC DRUGS — the group Datura Wrightii interacts with.

Datura wrightii contains atropine and scopolamine, as well as other tropane alkaloids with anticholinergic activity. Concomitant use of Datura wrightii with anticholinergic drugs might increase anticholinergic effects and adverse effects. Some anticholinergic drugs include amantadine, atropine, belladonna alkaloids, phenothiazines, scopolamine, and tricyclic antidepressants.
Severity Moderate Likelihood Probable Evidence D

Interaction 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..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the simple version. Datura wrightii is loaded with atropine and scopolamine, which are strong anticholinergic compounds, meaning they block the same nerve signals that diphenhydramine (the antihistamine in Actifed Allergy) already blocks. Stack them together and you essentially double down on that drying, slowing effect. You could end up with a very dry mouth, blurry vision, constipation, trouble urinating, a racing heart, confusion, and even hallucinations.

On top of that, the pseudoephedrine is a stimulant, so the combined heart-racing and overheating risk goes up. To be honest, I'd urge you not to use Datura wrightii at all, as it's genuinely poisonous. This concern is based on how these compounds work rather than direct studies, but the logic is solid. Please check with your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Adams, JD Jr, Garcia C. Spirit, Mind and Body in Chumash Healing. Evid Based Complement Alternat Med 2005;2(4):459-463. PubMed
  2. Evans WC, Woolley JG. The alkaloids of Datura meteloides D.C. J Chem Soc Perkin 1. 1965;4936-4939.

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

Datura Wrightii Also Interacts With Other Medications

Datura Wrightii has 225 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 225 No known interaction 2,605 (incl. Diphenhydramine, Pseudoephedrine)
Taking anything else?

Check Another of Your Medications Against Datura Wrightii

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

Everything else you take

See Every Supplement That Interacts With Diphenhydramine, Pseudoephedrine

This page covers Datura Wrightii 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

How much people look this up

Where Datura Wrightii 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 Datura Wrightii
Steady interest

#1,099 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Diphenhydramine, Pseudoephedrine
Steady interest

#1,798 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 Datura Wrightii

What is Datura Wrightii?

  • Traditional ritual and ceremonial use
  • Pain relief (traditional/topical)
  • Asthma and breathing complaints (historical)
  • Hallucinogenic/psychoactive effects
  • Skin and wound applications (folk use)

Datura wrightii (sacred datura or jimsonweed relative) is a highly poisonous desert plant that has been used in some traditional and ceremonial settings. It is not a safe dietary supplement — even small amounts can cause severe poisoning, hallucinations, and death. We strongly advise against using it.

Read the full Datura Wrightii monograph & all interactions
Keep checking

Other Drugs & Datura Wrightii

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

0Major
225Moderate
0Minor
2,604No known interaction
225 Moderate 2,604 No interaction
Moderate

225 interactions

Showing 60 of 225 moderate interactions — see all 225 on the Datura Wrightii page.

No interaction 2,604 drugs checked — show the list

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

Showing the 60 most looked-up of 2,604 medications checked with no known interaction — see the full Datura Wrightii list.

See the full Datura Wrightii 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
Datura Wrightii 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 Datura Wrightii and Diphenhydramine, Pseudoephedrine Together: Common Questions

Can you take Datura Wrightii 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 Datura Wrightii 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 Datura Wrightii?

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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.