There are multiple interactions reported between these two agents.

Interaction Details

Sofosbuvir, Velpatasvir is classified as belonging to the following category: P-Glycoprotein Substrates

Theoretically, milk thistle might increase the absorption of P-glycoprotein substrates. However, this effect does not seem to be clinically significant.
Although in vitro research shows that milk thistle can inhibit P-glycoprotein activity, clinical research does not agree. A small pharmacokinetic study in healthy volunteers shows that taking milk thistle (Enzymatic Therapy Inc.) 900 mg, standardized to 80% silymarin, in 3 divided doses daily for 14 days does not affect absorption of digoxin, a P-glycoprotein probe substrate.

Interaction Rating

Minor

Likelihood of Occurrence

Unlikely

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

References

  • Gurley, B. J., Barone, G. W., Williams, D. K., Carrier, J., Breen, P., Yates, C. R., Song, P. F., Hubbard, M. A., Tong, Y., and Cheboyina, S. Effect of milk thistle (Silybum marianum) and black cohosh (Cimicifuga racemosa) supplementation on digoxin phar
  • Derosa G, Romano D, D'Angelo A, Maffioli P. Berberis aristata/Silybum marianum fixed combination (Berberol(®)) effects on lipid profile in dyslipidemic patients intolerant to statins at high dosages: a randomized, placebo-controlled, clinical trial. Phyto

Interaction Details

Sofosbuvir, Velpatasvir is classified as belonging to the following category: Cytochrome P450 3A4 (Cyp3A4) Substrates

It is unclear if milk thistle inhibits CYP3A4; research is conflicting.
While laboratory research shows conflicting results, pharmacokinetic research shows that taking milk thistle extract 420-1350 mg daily does not significantly affect the metabolism of the CYP3A4 substrates irinotecan, midazolam, or indinavir.

Interaction Rating

Minor

Likelihood of Occurrence

Unlikely

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

References

  • Venkataramanan R, Ramachandran V, Komoroski BJ, et al. Milk thistle, a herbal supplement, decreases the activity of CYP3A4 and uridine diphosphoglucuronosyl transferase in human hepatocyte cultures. Drug Metab Dispos 2000;28:1270-3.
  • Piscitelli SC, Formentini E, Burstein AH, et al. Effect of milk thistle on the pharmacokinetics of indinavir in healthy volunteers. Pharmacotherapy 2002;22:551-6.
  • Sridar C, Goosen TC, Kent UM, et al. Silybin inactivates cytochromes P450 3A4 and 2C9 and inhibits major hepatic glucuronosyltransferases. Drug Metab Dispos 2004;32:587-94.
  • van Erp NP, Baker SD, Zhao M, et al. Effect of milk thistle (Silybum marianum) on the pharmacokinetics of irinotecan. Clin Cancer Res 2005;11:7800-6.
  • Budzinski JW, Trudeau VL, Drouin CE, et al. Modulation of human cytochrome P450 3A4 (CYP3A4) and P-glycoprotein (P-gp) in Caco-2 cell monolayers by selected commercial-source milk thistle and goldenseal products. Can J Physiol Pharmacol 2007;85:966-78.
  • Doehmer J, Weiss G, McGregor GP, Appel K. Assessment of a dry extract from milk thistle (Silybum marianum) for interference with human liver cytochrome-P450 activities. Toxicol In Vitro 2011;25:21-7.
  • 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.
  • Kawaguchi-Suzuki M, Frye RF, Zhu HJ, et al. The effects of milk thistle (Silybum marianum) on human cytochrome P450 activity. Drug Metab Dispos. 2014;42(10):1611-6.

Interaction Details

Sofosbuvir, Velpatasvir is classified as belonging to the following category: Sofosbuvir (Solvaldi)

Theoretically, milk thistle might decrease the levels and clinical effects of sofosbuvir.
Animal research in rats shows that milk thistle reduces the metabolism of sofosbuvir, as well as the hepatic uptake of its active metabolite.

Interaction Rating

Moderate

Likelihood of Occurrence

Possible

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

References

  • Aboras SI, Korany MA, El-Yazbi AF, Ragab MAA, Abdine HH. In-depth investigation of the Silymarin effect on the pharmacokinetic parameters of sofosbuvir, GS-331007 and ledipasvir in rat plasma using LC-MS. Biomed Chromatogr 2022;36(9):e5427.

Milk Thistle Overview

Milk Thistle Milk thistle (Silybum marianum) is a plant belonging to the aster family (Asteraceae). It is native to the Mediterranean region and is widely cultivated in many parts of the world. The plant is known for its milk-white veins on the leaves, which gives it its name. Milk thistle has a long history of use in traditional medicine, and is extremely popular as a dietary supplement, making it one of the most well-known plants in the world. It is purported to have liver-protectant effects and has been used to treat liver disorders such as hepatitis and cirrhosis. It has also been used to treat gallbladder problems and high cholesterol. While there are a number of compounds in milk thistle, one of the active constituents, silymarin, is thought to be responsible for many of its effects, and dietary supplements often report using a standardized amount (generally 70% to 80% silymarin in extracts).
See More Information Regarding Milk Thistle

Sofosbuvir, Velpatasvir Overview

  • The combination of sofosbuvir and velpatasvir is used alone or with ribavirin (Copegus, Rebetol, Ribasphere) to treat chronic hepatitis C (an ongoing viral infection that damages the liver) in adults and children 6 years of age and older or who weigh at least 37 lbs (17 kg). Sofosbuvir is in a class of antiviral medications called nucleotide hepatitis C virus (HCV) NS5B polymerase inhibitors. Velpatasvir is in a class of antiviral medications called HCV NS5A replication complex inhibitors. The combination of sofosbuvir and velpatasvir works by stopping the virus that causes hepatitis C from spreading inside the body.

See More Information Regarding Sofosbuvir and Velpatasvir

Milk Thistle - More Interactions

Milk Thistle interacts with 865 drugs

Interaction Rating Key

These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.

Major The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur.
Moderate Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur.
Minor Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction.
Unknown No interactions have been reported or no interaction data is currently available.

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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

Drug descriptions are provided by MedlinePlus.

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Dr. Brian Staiger, PharmD

In addition to being a clinical pharmacist specializing in pharmacotherapy, Dr. Brian Staiger is a registered herbalist through the American Herbalist Guild. He has combined his passion for pharmacy practice with the study of medical ethnobotany to improve patient care. Feel free to reach out about any of your herbal or medication questions!

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