How can ritonavir and itraconazole interact with betamethasone valerate in Betnovate Cream?

Ritonavir and itraconazole inhibit CYP3A4 and can reduce corticosteroid metabolism, increasing systemic exposure to betamethasone valerate in Betnovate Cream; clinical relevance depends on the corticosteroid dose and route of administration and the CYP3A4 inhibitor’s potency.