Abstract: Reported one case of drug incompatibility in the treatment of clinical transfusion. Incompatibility of bromhexine hydrochloird with methyprednisolone sodium succinate for injection was confirmed after repeated test. It may be releated to the chemical properties of bromhexine hydrochloird and pharmaceutical excipients of methyprednisolone sodium succinate. Clinical sequential infusion therapy in addition to attention to compatibility, should also pay attention to flush or replace the the infusion, to prevent medical accidents.