Drug & supplement interaction

Vitamin A + etretinate

etretinate brand name: Tegison.

Major Interaction
Medically reviewed by · Updated October 2026
The bottom line Major

Vitamin A has a major interaction with etretinate. Concomitant use of retinoids with vitamin A supplements might produce supratherapeutic vitamin A levels.

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

Vitamin A and etretinate

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

Major

RETINOIDS

Why this applies to etretinate

etretinate falls under RETINOIDS — the group Vitamin A interacts with.

Concomitant use of retinoids with vitamin A supplements might produce supratherapeutic vitamin A levels.
Retinoids, which are vitamin A derivatives, could have additive toxic effects when taken with vitamin A supplements.
Severity Major 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: etretinate (Tegison) is itself a vitamin A relative, a retinoid used for severe psoriasis. So when you add a vitamin A supplement on top of it, you're essentially stacking vitamin A on more vitamin A. The two don't cancel out, they pile up.

That stacking can push you toward vitamin A toxicity, with things like dry, cracking lips and skin, headaches, hair thinning, achy joints or bones, and irritated eyes, basically exaggerated versions of what etretinate already tends to cause. This concern is based on how these compounds behave (pharmacology) rather than hard human studies, but because both are fat-soluble and can build up, it's worth taking seriously. Please don't start a vitamin A supplement without checking with your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.

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

Vitamin A Also Interacts With Other Medications

Vitamin A has 8 major, 380 moderate known drug interactions in our database — the etretinate one above is one of them. If you take anything else, check it against the full list below.

Major 8 Moderate 380 No known interaction 2,442 (incl. etretinate)
Taking anything else?

Check Another of Your Medications Against Vitamin A

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

From our Q&A

Questions About Vitamin A or etretinate

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

This page covers Vitamin A only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the etretinate page lists 38 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Alfalfa (moderate), Angelica Archangelica (moderate), Arrach (moderate) and Bergamot (moderate).

By severity: 2 major · 26 moderate · 10 minor.

From our pharmacist’s overview on the etretinate page

“Vitamin A supplements are the first thing I would take off the shelf for anyone on etretinate (Tegison). Etretinate, a psoriasis medicine, is itself a vitamin A derivative, so supplementing on top of it can push levels toward toxicity.”

Reviewed by 2 · Jul 18, 2026

Open the etretinate interaction page

One more smart check

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

We hold 19,215 real supplement products containing Vitamin A, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Vitamin A. Your product may carry other ingredients that interact with etretinate too, on top of Vitamin A — 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 Vitamin A and etretinate 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 Vitamin A
Top 10

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

29 days ago today
Medication etretinate
Steady interest

#2,321 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 Vitamin A

What is Vitamin A?

  • Eye and vision health
  • Skin health and acne
  • Immune support
  • Correcting vitamin A deficiency
  • Childhood growth and development

Vitamin A is an essential nutrient important for vision, skin, immune function, and growth. Most people get enough from a balanced diet, and supplements are mainly useful for correcting a true deficiency. Because vitamin A is fat-soluble and can build up to harmful levels, more is not better, and high doses are especially risky in pregnancy.

Read the full Vitamin A monograph & all interactions
Keep checking

Other Drugs & Vitamin A

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

8Major
380Moderate
0Minor
2,441No known interaction
8 Major 380 Moderate 2,441 No interaction
Major

8 interactions

Moderate

380 interactions

Showing 60 of 380 moderate interactions — see all 380 on the Vitamin A page.

No interaction 2,441 drugs checked — show the list

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

Showing the 60 most looked-up of 2,441 medications checked with no known interaction — see the full Vitamin A list.

See the full Vitamin A interactions page
See every supplement checked against etretinate, 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
Vitamin A monograph › Uses, safety, and every drug interaction in one place etretinate supplement interactions › Every supplement checked against etretinate, 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 Vitamin A and etretinate Together: Common Questions

Can you take Vitamin A with etretinate?
This is rated a major interaction, so the combination is best avoided unless your doctor or pharmacist has specifically told you otherwise. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Vitamin A and etretinate interaction?
We rate it Major. This is a clinically significant combination that is generally best avoided, or used only under the direct supervision of your physician or pharmacist.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About etretinate and Vitamin A?

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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.