Drug & supplement interaction

Wild Lettuce + Chlorpromazine

Chlorpromazine brand names: Thorazine, Thorazine Spansules.

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

Chlorpromazine falls into 2 drug categories that Wild Lettuce can interact with; the most serious is rated moderate. Theoretically, concomitant use with drugs with sedative effects might cause additive therapeutic effects and adverse effects.

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

Wild Lettuce and Chlorpromazine

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

Why Are There 2 Interactions?

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

Moderate

CNS DEPRESSANTS

1 of 2

Why this applies to Chlorpromazine

Chlorpromazine falls under CNS DEPRESSANTS — the group Wild Lettuce interacts with.

Theoretically, concomitant use with drugs with sedative effects might cause additive therapeutic effects and adverse effects.
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: Chlorpromazine already has a strong calming, sedating side to it. It can make you feel drowsy, foggy, dizzy, or lightheaded when you stand up. Wild lettuce is taken mostly for sleep and relaxation, so the worry is that the two together could pile on each other and leave you more sedated than you expect.

I'll be honest with you, this concern is theoretical. It's based on how both work, not on solid studies in people, so we don't know how often it actually causes trouble. Still, since extra drowsiness with chlorpromazine can affect your balance and driving, it's worth a quick chat with your pharmacist or doctor before combining them rather than guessing.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
Moderate

ANTICHOLINERGIC DRUGS

2 of 2

Chlorpromazine also falls under ANTICHOLINERGIC DRUGS.

Studies report varying evidence on whether or not wild lettuce contains hyoscyamine, an anticholinergic drug. If it does, it appears to be in very low amounts. Nevertheless, there have been case reports of individuals consuming large amounts of wild lettuce experiencing anticholinergic-related side effects, such as constipation, dry mouth, dizziness, and sweating. Therefore, if you are already taking a drug with anticholinergic effects, you should be cautious about combining it with wild lettuce as the risk of side effects may be increased.
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 practical takeaway. Chlorpromazine already has its own anticholinergic, or 'drying,' side effects. That's why people on it often deal with a dry mouth, constipation, blurred vision, dizziness, and trouble emptying the bladder. Wild lettuce may add a little anticholinergic activity of its own, though the evidence here is shaky. Some sources question whether it even contains those compounds, and if it does, the amounts look very small.

The real-world concern shows up when someone takes large amounts of wild lettuce. Stacking it on top of chlorpromazine could nudge those drying effects up a notch, so you might notice more dry mouth, constipation, or lightheadedness. The interaction isn't strong or well proven, but it's worth a quick chat with your pharmacist or doctor before combining them.

Contact Dr. Brian directly if you have additional questions on this interaction

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

Wild Lettuce Also Interacts With Other Medications

Wild Lettuce has 392 moderate known drug interactions in our database — the Chlorpromazine one above is among them. If you take anything else, check it against the full list below.

Moderate 392 No known interaction 2,438 (incl. Chlorpromazine)
Taking anything else?

Check Another of Your Medications Against Wild Lettuce

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

From our Q&A

Questions About Wild Lettuce or Chlorpromazine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Wild Lettuce or Chlorpromazine, 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 Chlorpromazine

This page covers Wild Lettuce only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Chlorpromazine page lists 211 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), American Hellebore (major), Arsenic (major) and Beer (major).

By severity: 17 major · 159 moderate · 35 minor.

Open the Chlorpromazine interaction page

One more smart check

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

We hold 99 real supplement products containing Wild Lettuce, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Wild Lettuce. Your product may carry other ingredients that interact with Chlorpromazine too, on top of Wild Lettuce — 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 Wild Lettuce and Chlorpromazine 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 Wild Lettuce
Steady interest

#1,153 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Chlorpromazine
Steady interest

#1,823 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 Wild Lettuce

What is Wild Lettuce?

Wild Lettuce
  • Insomnia and trouble sleeping
  • Anxiety and restlessness
  • Pain relief
  • Cough and respiratory symptoms
  • Muscle spasms

Wild lettuce is a traditional herb used mainly for sleep, anxiety, and pain, but solid human research supporting these uses is very limited. Because its safety is not well studied, it should be used cautiously, avoided in pregnancy and breastfeeding, and discussed with your pharmacist or doctor first.

Read the full Wild Lettuce monograph & all interactions
Medication

About Chlorpromazine

What Is Chlorpromazine Used For?

Brand names: Thorazine, Thorazine Spansules

Chlorpromazine is used to manage psychotic disorders and treat schizophrenia. It also controls nausea and vomiting, relieves restlessness and apprehension before surgery, and controls the manic phase of manic-depressive illness. Other uses include relief of intractable hiccups, treatment of acute intermittent porphyria, and use as an adjunct in tetanus treatment.

In children ages 1 to 12, it is used for severe behavioral problems marked by explosive or combative behavior, and for short-term treatment of hyperactive children with conduct disorders. The oral forms are also approved for the management of manifestations of psychotic disorders broadly, in addition to the uses shared with the injection form.

See full Chlorpromazine drug information
Keep checking

Other Drugs & Wild Lettuce

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

0Major
392Moderate
0Minor
2,437No known interaction
392 Moderate 2,437 No interaction
Moderate

392 interactions

Showing 60 of 392 moderate interactions — see all 392 on the Wild Lettuce page.

No interaction 2,437 drugs checked — show the list

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

Showing the 60 most looked-up of 2,437 medications checked with no known interaction — see the full Wild Lettuce list.

See the full Wild Lettuce interactions page
See every supplement checked against Chlorpromazine, 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
Wild Lettuce monograph › Uses, safety, and every drug interaction in one place Chlorpromazine supplement interactions › Every supplement checked against Chlorpromazine, ranked by severity Chlorpromazine 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 Wild Lettuce and Chlorpromazine Together: Common Questions

Can you take Wild Lettuce with Chlorpromazine?
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 Wild Lettuce and Chlorpromazine?
Chlorpromazine belongs to more than one drug category, and Wild Lettuce 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 Wild Lettuce and Chlorpromazine 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 Chlorpromazine and Wild Lettuce?

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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.