Does epclusa interact with antacids or ppis?

Epclusa interacts with both antacids and PPIs, but the interaction mechanism and required timing differ.
Antacids containing aluminum or magnesium reduce absorption of sofosbuvir and velpatasvir, the two active ingredients in Epclusa.
PPIs lower stomach pH and impair velpatasvir absorption, decreasing overall drug levels.

How should you time antacids around Epclusa doses?
Take Epclusa four hours before or four hours after aluminum- or magnesium-containing antacids.
Calcium-based antacids require a two-hour separation.

What happens if you take PPIs with Epclusa?
The label permits omeprazole 20 mg once daily taken at the same time as Epclusa.
Higher omeprazole doses or other PPIs may lower velpatasvir exposure below therapeutic levels.

Can you switch to a different acid-reducing medicine?
H2-receptor antagonists such as famotidine 40 mg twice daily can be used, provided they are taken 12 hours apart from Epclusa.
Antacids or H2 blockers are often preferred over PPIs when acid suppression is still required.

Why does the interaction matter for treatment success?
Reduced velpatasvir levels raise the risk of treatment failure and resistance in hepatitis C genotypes 1–6.
Maintaining consistent spacing or dose adjustment prevents sub-therapeutic exposure.

Do any clinical studies quantify the interaction?
Pharmacokinetic studies show velpatasvir AUC drops 50–60 % when co-administered with omeprazole 40 mg, confirming the need for strict timing or PPI dose limits.