Yes, it is safe to use these treatments together, and they actually complement each other. The medicated shampoo containing ketoconazole and salicylic acid works to clear the psoriasis scales and reduce scalp inflammation. Clearing these scales is crucial because it allows the 10% minoxidil topical solution to penetrate your scalp more effectively to treat the hair loss. For best results, wash your hair with the shampoo first, dry your scalp completely, and then apply the minoxidil solution. Controlling the scalp psoriasis is a key step in managing your hair fall. Please continue to consult your dermatologist to monitor your progress.