Can Wellbutrin Be Prescribed with Sofosbuvir-Velpatasvir?
Yes, bupropion (Wellbutrin) can be safely prescribed concurrently with sofosbuvir-velpatasvir, as there is no clinically significant drug interaction between these medications.
Pharmacologic Rationale
Bupropion is primarily metabolized by CYP2B6 and is also a substrate and inhibitor of CYP2D6 1. Sofosbuvir-velpatasvir's interaction profile is well-defined: velpatasvir undergoes slow metabolic turnover by CYP2B6, CYP2C8, and CYP3A4, while both sofosbuvir and velpatasvir are substrates of P-gp and BCRP transporters 2.
The critical distinction here is that bupropion is neither a potent P-gp inducer nor a potent CYP inducer—the two mechanisms that would contraindicate use with sofosbuvir-velpatasvir 3. The EASL guidelines specifically list contraindicated drugs as potent P-gp or CYP inducers such as rifampicin, carbamazepine, phenobarbital, phenytoin, and St. John's wort 3. Bupropion does not appear on this list.
Key Interaction Considerations
What Sofosbuvir-Velpatasvir Actually Affects:
- Velpatasvir inhibits P-gp, BCRP, OATP1B1, OATP1B3, and OATP2B1 transporters 2
- This means sofosbuvir-velpatasvir can increase exposure of drugs that are substrates of these transporters
- Bupropion is not a substrate of these transporters in a clinically meaningful way
What Could Theoretically Happen:
Since velpatasvir has slow metabolic turnover by CYP2B6 and bupropion is metabolized by CYP2B6, there could theoretically be minor competitive metabolism. However, the FDA label for sofosbuvir-velpatasvir explicitly states that it "may be coadministered with P-gp, BCRP, and CYP inhibitors" 2, and bupropion acts primarily as a CYP2D6 inhibitor, not a CYP2B6 inhibitor.
Clinical Bottom Line
No dose adjustment is needed for either medication when prescribed together. The absence of bupropion from both the EASL contraindicated/cautionary drug lists 3 and the FDA drug interaction tables 2 indicates no clinically significant interaction exists.
Important Caveats:
- Monitor for standard bupropion side effects (seizure risk, neuropsychiatric effects) as you would in any patient 1
- Ensure the patient is not on other medications that lower seizure threshold when adding bupropion 1
- The hepatitis C treatment itself may alter hepatic function, which could theoretically affect drug metabolism, but this is not specific to bupropion and applies to all concomitant medications 2
This combination is safe to prescribe without special monitoring beyond standard clinical care for each medication individually.