Drug & supplement interaction

Gymnema + Sofosbuvir, Velpatasvir, Voxilaprevir

Sofosbuvir, Velpatasvir, Voxilaprevir brand name: Vosevi.

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

Sofosbuvir, Velpatasvir, Voxilaprevir falls into 2 drug categories that Gymnema can interact with; the most serious is rated moderate. Theoretically, gymnema might increase levels 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

Gymnema and Sofosbuvir, Velpatasvir, Voxilaprevir

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

Why Are There 2 Interactions?

Gymnema interacts with whole categories of medication. Sofosbuvir, Velpatasvir, Voxilaprevir falls into 2 of those categories, so it can interact with Gymnema 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 Gymnema interacts with.

Theoretically, gymnema might increase levels of drugs metabolized by CYP1A2.
Animal and in vitro research shows that gymnema can inhibit the CYP1A2 enzyme. In one animal study, oral administration of gymnema for 7 days increased the plasma concentrations of phenacetin, a CYP1A2 substrate, by about 1.4-fold and reduced the clearance of phenacetin by about 29%.
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 gymnema. The concern on file is that gymnema may block a liver enzyme called CYP1A2. In theory, slowing that enzyme could let a medicine that depends on it build up a bit. But this idea comes only from animal and test-tube studies, not from people taking gymnema with this exact hepatitis C combination, so it stays fairly theoretical.

For your treatment, the bigger reason to be careful is simpler: finishing this regimen exactly as prescribed is what clears the virus. I wouldn't want any added supplement to risk that, or to add stomach upset, tiredness, or headache. Please check with your pharmacist or doctor before adding gymnema, especially since it can also lower blood sugar.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Rammohan B, Samit K, Chinmoy D, et al. Human cytochrome P450 enzyme modulation by gymnema sylvestre: a predictive safety evaluation by LC-MS/MS. Pharmacogn Mag. 2016 Jul;12(Suppl 4):S389-S394.
  2. Vaghela M, Sahu N, Kharkar P, Pandita N. In vivo pharmacokinetic interaction by ethanolic extract of gymnema sylvestre with CYP2C9 (tolbutamide), CYP3A4 (amlodipine) and CYP1A2 (phenacetin) in rats. Chem Biol Interact. 2017 Dec 25;278:141-151. PubMed
  3. Vaghela M, Iyer K, Pandita N. In vitro inhibitory effect of gymnema sylvestre extracts and total gymnemic acids fraction on select cytochrome P450 activities in rat liver microsomes. Eur J Drug Metab Pharmacokinet. 2017 Oct 10. PubMed
Minor

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

2 of 2

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

Theoretically, gymnema might increase levels of drugs metabolized by CYP3A4.
One in vitro study using rat liver microsomes shows that gymnema can modestly inhibit the CYP3A4 enzyme. However, other in vitro research using human liver microsomes shows that gymnema does not affect CYP3A4 activity. Animal research also shows that gymnema does not alter the function of CYP3A4. In one study in rats, oral administration of gymnema for 7 days did not alter the clearance of amlodipine, a CYP3A4 substrate.
Severity Minor Likelihood Unlikely Evidence D

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the gist for folks on Vosevi (sofosbuvir, velpatasvir, voxilaprevir): part of this combo, especially the voxilaprevir piece, is handled by a liver enzyme called CYP3A4. The thought is that gymnema might slow that enzyme a little, which in theory could let drug levels creep up and possibly add to side effects like headache, tiredness, nausea, or diarrhea.

The honest part: this concern comes only from a single lab dish study using rat tissue. Other lab and animal work showed gymnema didn't affect CYP3A4 at all, so a real-world problem here is unlikely. Still, finishing your full hepatitis C course exactly as prescribed matters a lot, so check with your pharmacist or doctor before adding gymnema.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Rammohan B, Samit K, Chinmoy D, et al. Human cytochrome P450 enzyme modulation by gymnema sylvestre: a predictive safety evaluation by LC-MS/MS. Pharmacogn Mag. 2016 Jul;12(Suppl 4):S389-S394.
  2. Vaghela M, Sahu N, Kharkar P, Pandita N. In vivo pharmacokinetic interaction by ethanolic extract of gymnema sylvestre with CYP2C9 (tolbutamide), CYP3A4 (amlodipine) and CYP1A2 (phenacetin) in rats. Chem Biol Interact. 2017 Dec 25;278:141-151. PubMed
  3. Vaghela M, Iyer K, Pandita N. In vitro inhibitory effect of gymnema sylvestre extracts and total gymnemic acids fraction on select cytochrome P450 activities in rat liver microsomes. Eur J Drug Metab Pharmacokinet. 2017 Oct 10. 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

Gymnema Also Interacts With Other Medications

Gymnema has 347 moderate, 505 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.

Moderate 347 Minor 505 No known interaction 1,978 (incl. Sofosbuvir, Velpatasvir, Voxilaprevir)
Taking anything else?

Check Another of Your Medications Against Gymnema

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

Everything else you take

See Every Supplement That Interacts With Sofosbuvir, Velpatasvir, Voxilaprevir

This page covers Gymnema 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 Gymnema as Part of a Dietary Supplement Product? Check It for Interactions

We hold 1,084 real supplement products containing Gymnema, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Gymnema. Your product may carry other ingredients that interact with Sofosbuvir, Velpatasvir, Voxilaprevir too, on top of Gymnema — 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 Gymnema 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 Gymnema
Top 25%

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

29 days ago today
Medication Sofosbuvir, Velpatasvir, Voxilaprevir
Top 25%

#318 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 Gymnema

What is Gymnema?

Gymnema
  • Blood sugar support
  • Type 2 diabetes
  • Sugar cravings
  • Weight management
  • Cholesterol support

Gymnema is an Ayurvedic herb best known for possibly helping lower blood sugar and reducing the taste of sweetness on the tongue. Some early human studies are encouraging for blood sugar support, but the evidence is still limited and not strong enough to replace standard treatment. If you have diabetes or take other medicines, talk with your pharmacist or doctor before using it.

Read the full Gymnema 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 without cirrhosis (liver scarring) or with compensated cirrhosis (mild liver scarring, Child-Pugh A). It is specifically for people who have already tried an HCV treatment that did not fully work.

Vosevi is approved for adults with HCV genotypes 1, 2, 3, 4, 5, or 6 who were previously treated with a regimen containing an NS5A inhibitor. It is also approved for adults with genotype 1a or 3 who were previously treated with sofosbuvir without an NS5A inhibitor. Note: Vosevi has not been shown to offer additional benefit over sofosbuvir/velpatasvir for adults with genotype 1b, 2, 4, 5, or 6 who received sofosbuvir without an NS5A inhibitor.

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

Other Drugs & Gymnema

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

0Major
347Moderate
505Minor
1,977No known interaction
347 Moderate 505 Minor 1,977 No interaction
Moderate

347 interactions

Showing 60 of 347 moderate interactions — see all 347 on the Gymnema page.

Minor

505 interactions

Showing 60 of 505 minor interactions — see all 505 on the Gymnema page.

No interaction 1,977 drugs checked — show the list

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

Showing the 60 most looked-up of 1,977 medications checked with no known interaction — see the full Gymnema list.

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

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