Drug & supplement interaction

Kratom + Sofosbuvir, Velpatasvir, Voxilaprevir

Sofosbuvir, Velpatasvir, Voxilaprevir brand name: Vosevi.

Moderate Interaction
The bottom line Moderate

Sofosbuvir, Velpatasvir, Voxilaprevir falls into 2 drug categories that Kratom can interact with; the most serious is rated moderate. Theoretically, kratom might increase the levels and clinical effects of drugs metabolized by CYP1A2.

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

Kratom and Sofosbuvir, Velpatasvir, Voxilaprevir

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

Why Are There 2 Interactions?

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

Moderate

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

1 of 2

Why this applies to Sofosbuvir, Velpatasvir, Voxilaprevir

Sofosbuvir, Velpatasvir, Voxilaprevir falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Kratom interacts with.

Theoretically, kratom might increase the levels and clinical effects of drugs metabolized by CYP1A2.
In vitro research suggests that kratom extract inhibits the activity of CYP1A2. In one case report, a 63-year-old male presented with possible serotonin syndrome after taking an unknown dose of kratom for up to 3 months along with serotonergic prescription medications bupropion, buspirone, desvenlafaxine, trazodone, and ziprasidone. It was hypothesized that kratom inhibited CYP1A2-mediaed metabolism of ziprasidone which consequently increased systemic exposure to serotonin.
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 honest picture with Vosevi (sofosbuvir, velpatasvir, voxilaprevir) and kratom. The concern on file is that kratom may block a liver enzyme called CYP1A2. In theory, slowing that enzyme could let certain drugs build up to higher levels. But this is based only on lab (test-tube) data, not on real studies in people taking Vosevi, so it's a fairly soft, theoretical worry.

To be fair, Vosevi is cleared mainly through other pathways (CYP3A4 and transporters), so CYP1A2 isn't its big route. My bigger worry is kratom itself: it strains the liver, and you're treating a liver infection. Please don't add kratom while on hepatitis C therapy without checking with your pharmacist or doctor first.

References
  1. Kong WM, Chik Z, Ramachandra M, et al. Evaluation of the effects of Mitragyna speciosa alkaloid extract on cytochrome P450 enzymes using a high throughput assay. Molecules. 2011;16(9):7344-7356. PubMed
  2. Eudaley ST, Brooks SP, Hamilton LA. Case Report: Possible Serotonin Syndrome in a Patient Taking Kratom and Multiple Serotonergic Agents. J Pharm Pract 2022. PubMed
Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

2 of 2

Sofosbuvir, Velpatasvir, Voxilaprevir also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.

Kratom might increase the levels and clinical effects of drugs metabolized by CYP3A4.
In vitro research shows that kratom extract inhibits CYP3A4 enzyme activity. A pharmacokinetic study in adults shows that taking kratom tea 2 grams modestly increases the plasma concentration time-curve (AUC) and maximum concentration (Cmax) of CYP3A4 probe midazolam by 40-50% and its CYP3A4-mediated metabolites 18-27%. However, a lack of change in the half-life of midazolam and a simulation of the kratom-midazolam interaction suggest that kratom inhibits CYP3A4 enzymes in the small intestine but not the liver. Additionally, there is one case report of a 27-year-old male who died from neuroleptic malignant-like symptoms after concomitant use of kratom and quetiapine, a CYP3A4 substrate. Although it did not appear that the patient had consumed large quantities of quetiapine, postmortem plasma levels were in the lethal range, indicating possible inhibition of CYP3A4 by kratom. In another case report, a 63-year-old male presented with possible serotonin syndrome after taking an unknown dose of kratom for up to 3 months along with serotonergic prescription medications bupropion, buspirone, desvenlafaxine, trazodone, and ziprasidone. It is hypothesized that CYP3A4 inhibition by kratom reduced metabolism of desvenlafaxine, trazodone, and ziprasidone and consequently increased systemic exposure to serotonin.
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 connection with Vosevi (the sofosbuvir, velpatasvir, voxilaprevir combo you take for hepatitis C). Kratom appears to block an enzyme called CYP3A4, mostly in the gut. Voxilaprevir, one of the three medicines in Vosevi, is partly handled by that enzyme. So in theory, kratom could let a bit more of it build up in your blood, which might mean more chance of side effects like nausea, headache, tiredness, or diarrhea.

I want to be honest though: this is a theoretical concern based on lab work and a couple of case reports, not strong proof for this exact medicine. The bigger picture is that kratom itself isn't proven safe and can stress the liver, which already matters when you're treating hepatitis C. Please loop in your pharmacist or doctor before mixing the two.

References
  1. Kong WM, Chik Z, Ramachandra M, et al. Evaluation of the effects of Mitragyna speciosa alkaloid extract on cytochrome P450 enzymes using a high throughput assay. Molecules. 2011;16(9):7344-7356. PubMed
  2. Hughes RL. Fatal combination of mitragynine and quetiapine - a case report with discussion of a potential herb-drug interaction. Forensic Sci Med Pathol. 2019 Mar;15(1):110-113. PubMed
  3. Eudaley ST, Brooks SP, Hamilton LA. Case Report: Possible Serotonin Syndrome in a Patient Taking Kratom and Multiple Serotonergic Agents. J Pharm Pract 2022. PubMed
  4. Tanna RS, Nguyen JT, Hadi DL, et al. Clinical Assessment of the Drug Interaction Potential of the Psychotropic Natural Product Kratom. Clin Pharmacol Ther 2023;113(6):1315-1325. 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

Kratom Also Interacts With Other Medications

Kratom has 982 moderate, 12 minor known drug interactions in our database — the Sofosbuvir, Velpatasvir, Voxilaprevir one above is among them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Kratom

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

From our Q&A

Questions About Kratom or Sofosbuvir, Velpatasvir, Voxilaprevir

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Kratom or Sofosbuvir, Velpatasvir, Voxilaprevir, 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 Sofosbuvir, Velpatasvir, Voxilaprevir

This page covers Kratom only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Sofosbuvir, Velpatasvir, Voxilaprevir page lists 173 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 · 130 moderate · 40 minor.

From our pharmacist’s overview on the Sofosbuvir, Velpatasvir, Voxilaprevir page

“Vosevi (sofosbuvir, velpatasvir, and voxilaprevir) cures hepatitis C over a single short course, and that is exactly why I would be genuinely careful with supplements while taking it. Anything that drags its blood levels down can cost you the cure itself.”

Reviewed by 2 · Jul 18, 2026

Open the Sofosbuvir, Velpatasvir, Voxilaprevir interaction page

One more smart check

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

We hold 8 real supplement products containing Kratom, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Kratom. Your product may carry other ingredients that interact with Sofosbuvir, Velpatasvir, Voxilaprevir too, on top of Kratom — 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 Kratom and Sofosbuvir, Velpatasvir, Voxilaprevir 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 Kratom
Top 25%

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

29 days ago today
Medication Sofosbuvir, Velpatasvir, Voxilaprevir
Steady interest

#1,602 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 Kratom

What is Kratom?

Kratom
  • Pain relief
  • Opioid withdrawal symptoms
  • Anxiety and stress
  • Low energy or fatigue
  • Mood enhancement

Kratom is a Southeast Asian plant whose leaves act on the brain's opioid receptors and can produce both stimulant-like and opioid-like effects. It is not approved or proven safe by health regulators, carries real risks of dependence and serious harm, and its legal status varies widely. Talk to a pharmacist or doctor before considering it.

Read the full Kratom monograph & all interactions
Medication

About Sofosbuvir, Velpatasvir, and Voxilaprevir

What Is Sofosbuvir, Velpatasvir, and Voxilaprevir Used For?

Brand name: Vosevi

Vosevi is used to treat chronic hepatitis C virus (HCV) infection in adults who do not have cirrhosis or who have compensated cirrhosis (mild liver scarring that is still functioning). It is specifically for people who have already been treated with an HCV regimen before and need a different option.

Vosevi is approved for adults with HCV genotype 1, 2, 3, 4, 5, or 6 who previously took a medicine that included an NS5A inhibitor. It is also approved for adults with genotype 1a or 3 who previously took sofosbuvir without an NS5A inhibitor.

See full Sofosbuvir, Velpatasvir, and Voxilaprevir drug information
Keep checking

Other Drugs & Kratom

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

0Major
982Moderate
12Minor
1,835No known interaction
Moderate

982 interactions

Showing 60 of 982 moderate interactions — see all 982 on the Kratom page.

Minor

12 interactions

No interaction 1,835 drugs checked — show the list
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
Pharmacist Counseling Corner

Taking Kratom and Sofosbuvir, Velpatasvir, Voxilaprevir Together: Common Questions

Can you take Kratom with Sofosbuvir, Velpatasvir, Voxilaprevir?
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 Kratom and Sofosbuvir, Velpatasvir, Voxilaprevir?
Sofosbuvir, Velpatasvir, Voxilaprevir belongs to more than one drug category, and Kratom 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 Kratom and Sofosbuvir, Velpatasvir, Voxilaprevir 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

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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.