Epclusa Drug Interactions: What to Avoid and What to Tell Your Doctor

Epclusa (sofosbuvir/velpatasvir) has several important drug interactions that patients and providers need to be aware of before starting treatment. Some interactions are potentially life-threatening; others reduce Epclusa's effectiveness. This guide covers the most clinically significant interactions in plain language.

Always provide your doctor and pharmacist with a complete list of all prescription medications, over-the-counter drugs, vitamins, and supplements you take before starting Epclusa.

Interaction 1: Amiodarone — AVOID (Life-Threatening)

Amiodarone (brand names: Cordarone, Nexterone, Pacerone) is used to treat irregular heart rhythms (arrhythmias). Taking Epclusa with amiodarone can cause a serious, life-threatening slowing of the heart (symptomatic bradycardia). Cases have resulted in death or the need for a pacemaker.

This interaction is contraindicated — meaning it should be avoided entirely. If you take amiodarone and need Epclusa, talk to both your cardiologist and your HCV provider. There may be a way to transition off amiodarone first, but this requires careful medical management.

If you start Epclusa and then develop any of these symptoms, seek emergency care immediately: fainting, near-fainting, dizziness, extreme weakness, shortness of breath, or chest pain.

Interaction 2: Proton Pump Inhibitors (PPIs) — Avoid or Use Cautiously

PPIs include omeprazole (Prilosec), esomeprazole (Nexium), pantoprazole (Protonix), lansoprazole (Prevacid), and others. Because velpatasvir's absorption decreases significantly at higher stomach pH, PPIs — which raise stomach pH — can substantially reduce the amount of velpatasvir that gets into your bloodstream.

Coadministration is NOT recommended. If a PPI cannot be stopped:

• Use the lowest effective PPI dose (no more than omeprazole 20 mg/day or equivalent)
• Take Epclusa with food and take the PPI at the same time (simultaneously)

For antacids (Tums, Mylanta, Maalox): separate from Epclusa by at least 4 hours. For H2 blockers (famotidine/Pepcid, ranitidine): can be taken at the same time as Epclusa or 12 hours apart, at a dose no higher than famotidine 40 mg twice daily.

Interaction 3: Rifampin and Other Strong P-gp/CYP Inducers — AVOID

Drugs that strongly induce P-glycoprotein (P-gp) or CYP enzymes (2B6, 2C8, 3A4) can dramatically reduce blood levels of sofosbuvir and velpatasvir, making Epclusa ineffective. Drugs to avoid include:

• Rifampin (antibiotic/antitubercular) — major inducer; avoid
• Rifabutin, rifapentine — related to rifampin; avoid
• Carbamazepine (Tegretol) — anti-seizure; avoid
• Phenytoin (Dilantin) — anti-seizure; avoid
• Phenobarbital — anti-seizure/sedative; avoid
• St. John's Wort — herbal supplement; avoid entirely

Interaction 4: Certain HIV Medications — Monitor or Avoid

For patients with HCV/HIV coinfection, most antiretroviral drugs can be safely used with Epclusa. However, two specific HIV drugs are contraindicated:

• Efavirenz (Sustiva, and combination products like Atripla): Strong CYP inducer; substantially reduces velpatasvir levels. Avoid.
• Tipranavir/ritonavir: Strong P-gp inducer; avoid.

Tenofovir disoproxil fumarate (TDF) — found in many HIV regimens — can be used with Epclusa, but monitor for tenofovir-associated side effects (kidney and bone toxicity), as velpatasvir may increase TDF levels slightly.

Interaction 5: Topotecan — AVOID

Topotecan is a chemotherapy drug. Velpatasvir inhibits the BCRP and P-gp drug transporters, which significantly increases topotecan exposure and toxicity risk. Coadministration is not recommended.

Interaction 6: Statins — May Need Dose Adjustment

Velpatasvir inhibits OATP1B1 and OATP1B3 transporters, which can increase blood levels of some statins (cholesterol medications). Rosuvastatin (Crestor) and other statins that are substrates of these transporters may need dose adjustments or closer monitoring during Epclusa treatment. Tell your doctor if you take any statin medication.

Interaction 7: Other Heart Medications

Velsartan (Diovan) and other drugs that are substrates of OATP1B1/1B3/2B1 transporters may have increased exposure during Epclusa treatment. Monitor for signs of increased drug effect with these medications.

What to Tell Your Doctor Before Starting Epclusa

Before your first Epclusa prescription is filled, tell your provider about:

• All prescription medications, including heart, seizure, HIV, cancer, and psychiatric medications
• All over-the-counter drugs, including antacids, heartburn medications (PPIs, H2 blockers)
• All herbal supplements — especially St. John's Wort
• Any history of hepatitis B (for HBV reactivation screening)
• Any history of heart rhythm problems — especially if on amiodarone

For more details about Epclusa, see our guides on Epclusa side effects and what Epclusa is used for.