Drug & supplement interaction

Zinc + Nirmatrelvir, Ritonavir

Nirmatrelvir, Ritonavir brand name: Paxlovid.

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

Zinc has a moderate interaction with Nirmatrelvir, Ritonavir. Zinc modestly reduces levels of ritonavir.

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

Zinc and Nirmatrelvir, Ritonavir

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

Moderate

RITONAVIR (Norvir)

Zinc modestly reduces levels of ritonavir.
Clinical research shows that zinc might reduce serum ritonavir levels by chelating with ritonavir in the gut and preventing its absorption. In patients with HIV, ritonavir is taken with atazanavir to prevent the metabolism and increase the effects of atazanavir. A pharmacokinetic study shows that, in patients being treated with atazanavir/ritonavir, co-administration of zinc sulfate (Solvazinc tablets) 125 mg as a single dose or as multiple daily doses for 2 weeks reduces plasma levels of ritonavir by about 16%. However, atazanavir levels still remains high enough to prevent HIV virus replication. Therefore, the decrease in ritonavir levels is not likely to be clinically significant.
Severity Moderate Likelihood Probable Evidence B

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 gist for Paxlovid. The ritonavir part of this combo isn't really there to fight the virus on its own. Its job is to act as a 'booster,' slowing down how fast your body clears the nirmatrelvir so the antiviral stays at strong, effective levels. Zinc can bind to ritonavir in your gut and slightly reduce how much gets absorbed.

The good news is that the research we have suggests this dip is small (around 16% in studies with a similar booster setup) and was not enough to matter clinically. For a short 5-day Paxlovid course, this is unlikely to cause a problem. Still, since timing and full absorption matter, it's worth a quick chat with your pharmacist about spacing your zinc apart from your doses while you finish treatment.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Moyle G, Else L, Jackson A, Back D, Yapa MH, Seymour N, Ringner-Nackter L, Karolia Z, Gazzard B, Boffito M. Coadministration of atazanavir-ritonavir and zinc sulfate: impact on hyperbilirubinemia and pharmacokinetics. Antimicrob Agents Chemother. 2013 Aug PubMed
  2. Jalloh MA, Gregory PJ, Hein D, et al. Dietary supplement interactions with antiretrovirals: a systematic review. Int J STD AIDS. 2017 Jan;28(1):4-15. 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

Zinc Also Interacts With Other Medications

Zinc has 62 moderate, 4 minor known drug interactions in our database — the Nirmatrelvir, Ritonavir one above is one of them. If you take anything else, check it against the full list below.

Moderate 62 Minor 4 No known interaction 2,764 (incl. Nirmatrelvir, Ritonavir)
Taking anything else?

Check Another of Your Medications Against Zinc

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

Everything else you take

See Every Supplement That Interacts With Nirmatrelvir, Ritonavir

This page covers Zinc only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Nirmatrelvir, Ritonavir page lists 176 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Grapefruit (major), Siberian Cocklebur (major) and St. John's Wort (major).

By severity: 6 major · 134 moderate · 36 minor.

From our pharmacist’s overview on the Nirmatrelvir, Ritonavir page

“Paxlovid (nirmatrelvir and ritonavir) deserves genuine care around supplements, mostly because its ritonavir component strongly blocks the liver enzyme CYP3A4. The bulk of this list is made up of ingredients that enzyme normally clears, so their levels can climb unpredictably during the five-day course.”

Reviewed by 2 · Jul 18, 2026

Open the Nirmatrelvir, Ritonavir interaction page

One more smart check

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

We hold 26,692 real supplement products containing Zinc, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Zinc. Your product may carry other ingredients that interact with Nirmatrelvir, Ritonavir too, on top of Zinc — 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 Zinc and Nirmatrelvir, Ritonavir 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 Zinc
Top 10

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

29 days ago today
Medication Nirmatrelvir, Ritonavir
Top half

#878 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 Zinc

What is Zinc?

Zinc
  • Zinc deficiency
  • Immune support
  • Cold symptoms
  • Acne
  • Wound healing

Zinc is an essential mineral that your body needs for immune function, wound healing, taste, and smell. Most people get enough from food, but supplements can help correct or prevent a deficiency. Taking too much zinc for too long can cause harm, so check with a pharmacist or doctor before using high-dose supplements.

Read the full Zinc monograph & all interactions
Medication

About Nirmatrelvir and Ritonavir

What Is Nirmatrelvir and Ritonavir Used For?

Brand name: Paxlovid

Paxlovid is approved to treat mild-to-moderate COVID-19 in adults who are at high risk of progressing to severe disease — meaning hospitalization or death. It is intended for people who already have symptoms and a confirmed COVID-19 diagnosis.

Paxlovid is not approved to prevent COVID-19 before or after exposure. It is a treatment, not a preventive medication.

See full Nirmatrelvir and Ritonavir drug information
Keep checking

Other Drugs & Zinc

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

0Major
62Moderate
4Minor
2,763No known interaction
62 Moderate 4 Minor 2,763 No interaction
Moderate

62 interactions

Showing 60 of 62 moderate interactions — see all 62 on the Zinc page.

Minor

4 interactions

No interaction 2,763 drugs checked — show the list

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

Showing the 60 most looked-up of 2,763 medications checked with no known interaction — see the full Zinc list.

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

Can you take Zinc with Nirmatrelvir, Ritonavir?
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 Zinc and Nirmatrelvir, Ritonavir 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 Nirmatrelvir, Ritonavir and Zinc?

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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.