penicillin G benzathine

noun

penicillin G ben·​za·​thine -ˈben-zə-ˌthēn, -thən 

: an aqueous suspension of a relatively insoluble salt of penicillin G that is absorbed slowly following intramuscular injection to provide a low but persistent level of penicillin G in the blood plasma

called also benzathine penicillin G