Drug & supplement interaction

Passion Flower + Chloral Hydrate

Chloral Hydrate brand name: Chloral Hydrate.

Moderate Interaction
The bottom line Moderate

Passion Flower has a moderate interaction with Chloral Hydrate. Concomitant use of passion flower with sedative drugs might cause additive effects and side effects.

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

Passion Flower and Chloral Hydrate

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

Moderate

CNS DEPRESSANTS

Why this applies to Chloral Hydrate

Chloral Hydrate falls under CNS DEPRESSANTS — the group Passion Flower interacts with.

Concomitant use of passion flower with sedative drugs might cause additive effects and side effects.
Research in animals and humans shows that passion flower has sedative effects which can be additive when used with sedative medications like lorazepam.
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: chloral hydrate is already a strong sedative, the kind used to bring on sleep before a procedure or to settle alcohol withdrawal. Passion flower is a mild calming herb that's thought to nudge up GABA, the same brain chemical that quiets nerve activity. Stack the two and their relaxing effects can pile on top of each other.

In real life that could mean feeling more drowsy, lightheaded, foggy, or unsteady than you expected, with slower breathing being the bigger worry. This concern is mostly theoretical, based on how both work rather than reports of harm, but chloral hydrate is potent enough that I wouldn't combine them on your own. Please check with your pharmacist or doctor first.

References
  1. Akhondzadeh S, Naghavi HR, Shayeganpour A, et al. Passionflower in the treatment of generalized anxiety: a pilot double-blind randomized controlled trial with oxazepam. J Clin Pharm Ther 2001;26:363-7. PubMed
  2. Speroni E., Minghetti A. Neuropharmacological activity of extracts from Passiflora incarnata. Planta Med. 1988;54:488-91.
  3. Capasso A., Sorrentino L. Pharmacological studies on the sedative and hypnotic effect of Kava kava and Passiflora extracts combination. Phytomedicine. 2005;12:39-45. PubMed
  4. Carrasco MC, Vallejo JR, Pardo-de-Santayana M, et al. Interactions of Valeriana officinalis L. and Passiflora incarnata L. in a patient treated with lorazepam. Phytother Res. 2009 Dec;23:1795-6.
  5. Soulimani, R., Younos, C., Jarmouni, S., Bousta, D., Misslin, R., and Mortier, F. Behavioural effects of Passiflora incarnata L. and its indole alkaloid and flavonoid derivatives and maltol in the mouse. J Ethnopharmacol. 1997;57(1):11-20. PubMed
  6. da Cunha RS, Amorim KS, Gercina AC, et al. Herbal medicines as anxiolytics prior to third molar surgical extraction. A randomized controlled clinical trial. Clin Oral Investig. 2020. 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

Passion Flower Also Interacts With Other Medications

Passion Flower has 247 moderate, 588 minor known drug interactions in our database — the Chloral Hydrate one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Passion Flower

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

From our Q&A

Questions About Passion Flower or Chloral Hydrate

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Passion Flower or Chloral Hydrate, 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 Chloral Hydrate

This page covers Passion Flower only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Chloral Hydrate page lists 95 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), Gamma-hydroxybutyrate (ghb) (major) and Kava (major).

By severity: 7 major · 73 moderate · 15 minor.

From our pharmacist’s overview on the Chloral Hydrate page

“Chloral hydrate is a sedative, prescribed to bring on sleep or to calm a patient before a procedure, and the supplements sleepless people reach for most (kava, ashwagandha, L-tryptophan) sit squarely on this list. Of the 95 ingredients with interactions on file, 78 add their own sedative pull to a drug that already slows the brain and…”

Reviewed by 2 · Jul 18, 2026

Open the Chloral Hydrate interaction page

One more smart check

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

We hold 2,129 real supplement products containing Passion Flower, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Passion Flower. Your product may carry other ingredients that interact with Chloral Hydrate too, on top of Passion Flower — 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 Passion Flower and Chloral Hydrate 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 Passion Flower
Top 10%

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

29 days ago today
Medication Chloral Hydrate
Steady interest

#1,930 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 Passion Flower

What is Passion Flower?

Passion Flower
  • Anxiety and stress
  • Trouble sleeping
  • Restlessness
  • Mild nervous tension
  • Muscle tension

Passion flower is a traditional calming herb that many people use for anxiety and sleep. Early studies hint it may help with mild anxiety and restlessness, but the evidence is limited and more research is needed. It is generally well tolerated short-term, but should be avoided in pregnancy and discussed with your pharmacist or doctor first.

Read the full Passion Flower monograph & all interactions
Keep checking

Other Drugs & Passion Flower

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

0Major
247Moderate
588Minor
1,994No known interaction
Moderate

247 interactions

Showing 60 of 247 moderate interactions — see all 247 on the Passion Flower page.

Minor

588 interactions

Showing 60 of 588 minor interactions — see all 588 on the Passion Flower page.

No interaction 1,994 drugs checked — show the list
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

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Pharmacist Counseling Corner

Taking Passion Flower and Chloral Hydrate Together: Common Questions

Can you take Passion Flower with Chloral Hydrate?
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 Passion Flower and Chloral Hydrate 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 Chloral Hydrate and Passion Flower?

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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.