Answer
Sildenafil is contraindicated with ritonavir in patients with pulmonary arterial hypertension because ritonavir's potent P450 inhibition markedly increases sildenafil blood concentrations and overall exposure.
Sources for this answer
- Revatio 20 mg Film-coated TabletsViatris (formerly Mylan or Upjohn) · emc · SmPC §4.5 Interaction with other medicinal products · Version 47Document updated
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