Drug & supplement interaction

L-citrulline + Bexarotene

Bexarotene brand name: Targretin.

No Known Interaction
The bottom line No known interaction

We found no known interaction between L-citrulline and Bexarotene in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the label for Bexarotene states a food rule worth keeping to, and the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

L-citrulline and Bexarotene

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Bexarotene and L-citrulline in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

L-citrulline safety at a glance

L-citrulline overall Use caution Generally well tolerated in healthy adults, but long-term safety is not fully studied.
Pregnancy Avoid There is not enough safety data, so it is best to avoid supplements during pregnancy.
Breastfeeding Avoid Safety while breastfeeding is unknown, so avoid supplemental use.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Bexarotene and L-citrulline? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Bexarotene

Interactions in our licensed database are recorded against drug classes, not just single drug names. Bexarotene is filed under 3 classifications — retinoids, cytochrome p450 3a4 (cyp3a4) substrates, oral drugs. L-citrulline has documented interactions with 2 drug classes — the most serious being antihypertensive drugs (moderate) and phosphodiesterase-5 inhibitors (moderate) — and none of Bexarotene’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

L-citrulline Does Interact With Other Medications

L-citrulline has 178 moderate known drug interactions in our database — Bexarotene isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against L-citrulline

Covers the 2,830 medications we’ve checked against L-citrulline. Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests L-citrulline and Bexarotene May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. One of them is worth acting on rather than waiting out — marked below.

  • Raised blood pressure Worth acting on Additional detail

    L-citrulline

    “Orally, 2 of 25 patients with pulmonary hypertension reported cough while taking 1 gram of powdered L-citrulline in water daily.”

    L-citrulline · Natural Medicines adverse-effect record, reported in cough.

    1 source cited
    1. 94963. Sharif Kashani B, Tahmaseb Pour P, Malekmohammad M, et al. Oral l-citrulline malate in patients with idiopathic pulmonary arterial hypertension and Eisenmenger Syndrome: a clinical trial. J Cardiol 2014;64:231-5. PubMed

    “Orally, 2 of 25 patients with pulmonary hypertension reported increased urinary frequency and edema while taking 1 gram of powdered L-citrulline in water daily.”

    L-citrulline · Natural Medicines adverse-effect record, reported in hypertension.

    1 source cited
    1. 94963. Sharif Kashani B, Tahmaseb Pour P, Malekmohammad M, et al. Oral l-citrulline malate in patients with idiopathic pulmonary arterial hypertension and Eisenmenger Syndrome: a clinical trial. J Cardiol 2014;64:231-5. PubMed

    Bexarotene

    Listed in the ADVERSE REACTIONS section of the FDA label for Bexarotene. Read the label on DailyMed ›

  • Cough Additional detail

    L-citrulline

    Recorded for L-citrulline in the same Natural Medicines adverse-effect record shown under Raised blood pressure above.

    Bexarotene

    Listed in the ADVERSE REACTIONS section of the FDA label for Bexarotene. Read the label on DailyMed ›

  • Stomach upset Additional detail

    L-citrulline

    “Orally, gastrointestinal intolerance, stomach discomfort, and heartburn have been reported with L-citrulline use.”

    L-citrulline · Natural Medicines adverse-effect record, reported in dyspepsia.

    3 sources cited
    1. 94955. Balderas-Munoz K, Castillo-Martínez L, Orea-Tejeda A, et al. Improvement of ventricular function in systolic heart failure patients with oral L-citrulline supplementation. Cardiol J 2012;19:612-7. PubMed
    2. 94963. Sharif Kashani B, Tahmaseb Pour P, Malekmohammad M, et al. Oral l-citrulline malate in patients with idiopathic pulmonary arterial hypertension and Eisenmenger Syndrome: a clinical trial. J Cardiol 2014;64:231-5. PubMed
    3. 94966. Pérez-Guisado J, Jakeman PM. Citrulline malate enhances athletic anaerobic performance and relieves muscle soreness. J Strength Cond Res 2010;24:1215-22. PubMed

    Bexarotene

    Listed in the ADVERSE REACTIONS section of the FDA label for Bexarotene. Read the label on DailyMed ›

  • Swelling Additional detail

    L-citrulline

    Recorded for L-citrulline in the same Natural Medicines adverse-effect record shown under Raised blood pressure above.

    Bexarotene

    Listed in the ADVERSE REACTIONS section of the FDA label for Bexarotene. Read the label on DailyMed ›

Reported for L-citrulline but not commonly for Bexarotene: heartburn.

Effects for Bexarotene come from the ADVERSE REACTIONS section of its FDA label; effects for L-citrulline come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

How to take them

Some Bexarotene Products Have a Food Rule — L-citrulline Should Not Break It

At least one FDA label for a product containing Bexarotene says to take it with food. If you take L-citrulline on an empty stomach out of habit, keep them separate — and take Bexarotene with a meal where the label says to.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Bexarotene products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.

TARGRETIN should be taken as a single oral daily dose with a meal.

From the Dosage and Administration section of the FDA label we read for Bexarotene — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›

A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.

From our Q&A

Questions About L-citrulline or Bexarotene

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers L-citrulline or Bexarotene, 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 Bexarotene

This page covers L-citrulline only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Bexarotene page lists 139 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Vitamin A (major) and Acacia Rigidula (moderate).

By severity: 4 major · 94 moderate · 41 minor.

Open the Bexarotene interaction page

One more smart check

Taking L-citrulline as Part of a Dietary Supplement Product? Check It for Interactions

We hold 63 real supplement products containing L-citrulline, each one broken down to its full ingredient list — and combination products often carry several ingredients besides L-citrulline. Even though L-citrulline itself has no known interaction with Bexarotene, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where L-citrulline and Bexarotene 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 L-citrulline
Top half

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

29 days ago today
Medication Bexarotene
Top 25%

#351 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every L-citrulline reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The L-citrulline and Bexarotene records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About L-citrulline

What is L-citrulline?

L-citrulline
  • Exercise performance
  • Muscle soreness and fatigue
  • Blood flow and circulation
  • Erectile dysfunction
  • Blood pressure support

L-citrulline is an amino acid that the body turns into L-arginine to help make nitric oxide, which relaxes blood vessels and may improve blood flow. It is popular for exercise performance and circulation, but the evidence is mixed and most benefits are modest. It appears generally well tolerated, but talk to your pharmacist or doctor before starting, especially if you have a health condition or are pregnant.

Amino acid (made by the body and found in foods; supplements are usually made by fermentation) · Powder, capsules, tablets; also sold as citrulline malate

An interaction check asks whether these two react with each other — it does not ask whether L-citrulline is a good idea for someone in your situation. Here is what our L-citrulline record says about it on its own.

L-citrulline: dosing

There is no official standardized dose of L-citrulline, and the right amount can depend on the form (plain L-citrulline versus citrulline malate) and the reason for use. Doses used in studies vary widely.Because of this, the best approach is to follow the directions on the product label and start with the lowest suggested amount.

From our L-citrulline monograph — the full record covers uses, side effects and every documented interaction.

Read the full L-citrulline monograph & all interactions
Medication

About Bexarotene

What Is Bexarotene Used For?

Brand name: Targretin

Bexarotene capsules (brands: Bexarotene, Targretin) are used to treat the skin symptoms of cutaneous T-cell lymphoma (CTCL) in patients whose disease has not responded to at least one prior systemic treatment.

Bexarotene gel 1% (brands: Bexarotene, Targretin) is used to treat the skin lesions of early-stage CTCL (Stage IA and IB) when other therapies have not worked or could not be tolerated. The gel is a topical therapy and is not intended for systemic use.

See full Bexarotene drug information
Keep checking

Other Drugs & L-citrulline

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

0Major
178Moderate
0Minor
2,651No known interaction
Moderate

178 interactions

Showing 60 of 178 moderate interactions — see all 178 on the L-citrulline page.

No interaction 2,651 drugs checked — show the list
Evidence & sources

L-citrulline References

The 8 references that drive our L-citrulline monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Cheng JW, Balwin SN. L-arginine in the management of cardiovascular diseases. Ann Pharmacother 2001;35:755-64. PubMed
  2. Schwedhelm E, Maas R, Freese R, et al. Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolism. Br J Clin Pharmacol 2008;65:51-9. PubMed
  3. Romero MJ, Platt DH, Caldwell RB, Caldwell RW. Therapeutic use of citrulline in cardiovascular disease. Cardiovasc Drug Rev 2006;24:275-90. PubMed
  4. Balderas-Munoz K, Castillo-Martínez L, Orea-Tejeda A, et al. Improvement of ventricular function in systolic heart failure patients with oral L-citrulline supplementation. Cardiol J 2012;19:612-7. PubMed
  5. Sharif Kashani B, Tahmaseb Pour P, Malekmohammad M, et al. Oral l-citrulline malate in patients with idiopathic pulmonary arterial hypertension and Eisenmenger Syndrome: a clinical trial. J Cardiol 2014;64:231-5. PubMed
  6. Pérez-Guisado J, Jakeman PM. Citrulline malate enhances athletic anaerobic performance and relieves muscle soreness. J Strength Cond Res 2010;24:1215-22. PubMed
  7. Mirenayat MS, Moradi S, Mohammadi H, Rouhani MH. Effect of L-citrulline supplementation on blood pressure: a systematic review and meta-analysis of clinical trials. Curr Hypertens Rep. 2018;20(11):98. PubMed
  8. Xu Z, Liu C, Liu S, Zhou Z. Comparison of efficacy and safety of daily oral L-arginine and PDE5Is alone or combination in treating erectile dysfunction: A systematic review and meta-analysis of randomised controlled trials. Andrologia. 2021:e14007. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking L-citrulline and Bexarotene Together: Common Questions

Is it safe to take L-citrulline with Bexarotene?
We do not list a known interaction between L-citrulline and Bexarotene. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Do L-citrulline and Bexarotene have any of the same side effects?
Yes — our sources link each of them separately to 4 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Should I take L-citrulline and Bexarotene at the same time of day?
At least one FDA label for a product containing Bexarotene says to take it with food. If you take L-citrulline on an empty stomach out of habit, keep them separate and take Bexarotene with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Bexarotene products can differ — so check the directions on your own box. This is about absorption, not an interaction.
How was the L-citrulline and Bexarotene combination checked?
Interactions in our licensed database are recorded against drug classes. Bexarotene is filed under 3 classifications, and L-citrulline has documented interactions with 2 drug classes — none of Bexarotene's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does L-citrulline interact with any other medications?
Yes. L-citrulline has 178 documented drug interactions in our database — Bexarotene is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Bexarotene interact with any supplements?
Yes. Bexarotene has documented interactions with 139 supplements in our database — L-citrulline is not one of them. The Bexarotene interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Bexarotene and L-citrulline?

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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.