Drug & supplement interaction

L-citrulline + Atazanavir

Atazanavir brand name: Reyataz.

No Known Interaction
The bottom line No known interaction

We found no known interaction between L-citrulline and Atazanavir 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 Atazanavir states a food rule worth keeping to.

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Interaction report

L-citrulline and Atazanavir

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 Atazanavir 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 Atazanavir and L-citrulline? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Atazanavir

Interactions in our licensed database are recorded against drug classes, not just single drug names. Atazanavir is filed under 7 classifications — including protease inhibitors (pis), cytochrome p450 2c9 (cyp2c9) inhibitors, cytochrome p450 1a2 (cyp1a2) inhibitors. L-citrulline has documented interactions with 2 drug classes — the most serious being antihypertensive drugs (moderate) and phosphodiesterase-5 inhibitors (moderate) — and none of Atazanavir’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 — Atazanavir 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

What L-citrulline Itself Has Been Linked To

This is not an interaction — nothing below involves Atazanavir. It is the side-effect record for L-citrulline on its own, from the licensed Natural Medicines monograph. If something new turns up after you add L-citrulline, this list is the first place to look. One entry is worth acting on rather than waiting out — marked below.

  • Raised blood pressure Worth acting on Additional detail

    “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
  • Heartburn / Stomach upset Additional detail

    “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
  • Cough Additional detail

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

  • Swelling Additional detail

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

Everything above comes from the Natural Medicines adverse-effect record for L-citrulline — expand a row for the licensed statement it rests on. We read the ADVERSE REACTIONS section of Atazanavir’s FDA label too, and the two lists don’t meaningfully overlap — which is why no Atazanavir column appears here.

How to take them

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

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

b For adult patients who cannot swallow the capsules, REYATAZ oral powder is taken once daily with food at the same recommended adult dosage as the capsules along with ritonavir.

From the Dosage and Administration section of the FDA label we read for Atazanavir — where that label names a specific product, the instruction is that product's. See the Atazanavir drug page ›

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 Atazanavir

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 Atazanavir, 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 Atazanavir

This page covers L-citrulline only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Atazanavir page lists 152 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), Acacia Rigidula (moderate) and Adrafinil (moderate).

By severity: 3 major · 107 moderate · 42 minor.

From our pharmacist’s overview on the Atazanavir page

“Atazanavir (Reyataz) treats HIV, and keeping its blood level steady is what stands between viral control and drug resistance, so I read this list with genuine care. Of the 152 supplement and herbal ingredients on file, three carry a major rating: St.”

Reviewed by 2 · Jul 18, 2026

Open the Atazanavir 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 Atazanavir, 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 Atazanavir 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

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

29 days ago today
Medication Atazanavir
Top 25%

#648 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 Atazanavir 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 Atazanavir

What Is Atazanavir Used For?

Brand name: Reyataz

Atazanavir capsules are used together with other antiretroviral medicines to treat HIV-1 infection in adults and in children 6 years and older who weigh at least 15 kg (about 33 lbs).

Reyataz — available as capsules and as an oral powder — is also approved for HIV-1 treatment in adults and in children as young as 3 months who weigh at least 5 kg (about 11 lbs). Reyataz oral powder must always be taken with ritonavir and food, and is not for use in children weighing less than 5 kg.

Most-Reported Side Effects for Atazanavir

From FAERS, the FDA’s public side-effect reporting system (14,470 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Depression 1,318 reports
Foetal exposure during pregnancy 1,048 reports
Anxiety 878 reports
Emotional distress 660 reports
Anhedonia 601 reports
See full Atazanavir 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 Atazanavir Together: Common Questions

Is it safe to take L-citrulline with Atazanavir?
We do not list a known interaction between L-citrulline and Atazanavir. 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.
Should I take L-citrulline and Atazanavir at the same time of day?
At least one FDA label for a product containing Atazanavir says to take it with food. If you take L-citrulline on an empty stomach out of habit, keep them separate and take Atazanavir with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Atazanavir products can differ — so check the directions on your own box. This is about absorption, not an interaction.
How was the L-citrulline and Atazanavir combination checked?
Interactions in our licensed database are recorded against drug classes. Atazanavir is filed under 7 classifications, and L-citrulline has documented interactions with 2 drug classes — none of Atazanavir'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 — Atazanavir 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 Atazanavir interact with any supplements?
Yes. Atazanavir has documented interactions with 152 supplements in our database — L-citrulline is not one of them. The Atazanavir 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 Atazanavir 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.