Sofosbuvir interacts with a defined set of drug classes, and is contraindicated in amiodarone co-therapy and untreated HBV co-infection. Screening for these before the first dose prevents almost all serious events.
Interaction classes to screen
| Class | Concern | Action |
|---|---|---|
| Metabolic inhibitors | Raised plasma levels and exaggerated effect | Reduce dose or space administration |
| Metabolic inducers | Reduced exposure and treatment failure | Review response and adjust |
| Same-target agents | Additive pharmacology | Avoid duplicate therapy |
| Agents affecting the same organ system | fatigue, headache, nausea, anaemia with ribavirin | Monitor and document |
Key takeaways
- Screen every new prescription against the patient's full medicine list.
- Common reactions, fatigue, headache, nausea, anaemia with ribavirin, are amplified by interacting drugs.
- Document the interaction check in the dispensing record.
- Re-screen whenever another long-term medicine is added.
Monitoring in practice
Most interaction risk is manageable with a scheduled review after the onset window of viral load falls within the first two weeks and one further check at steady state. Patients on multiple chronic medicines benefit from an annual structured medication review.
Sofosbuvir at a glance
| Attribute | Detail |
|---|---|
| Drug class | NS5B polymerase inhibitor antiviral |
| Common brand | Sovaldi / Hepcvir |
| Licensed use | chronic hepatitis C, in combination regimens |
| Available strengths | 400 mg |
| Dosage form | film-coated tablet |
| Typical onset | viral load falls within the first two weeks |
| Duration / dosing interval | 24-hour dosing |
| Storage | below 30 °C |