- The first widely used amine salt of penicillin G wasmade with procaine. Penicillin G procaine (Crysticillin,Duracillin, Wycillin) can be made readily from penicillin Gsodium by treatment with procaine hydrochloride. This saltis considerably less soluble in water than the alkali metalsalts, requiring about 250 mL to dissolve 1 g. Free penicillinis released only as the compound dissolves and dissociates.It has an activity of 1,009 units/mg. A large number ofpreparations for injection of penicillin G procaine are commerciallyavailable. Most of these are either suspensions inwater to which a suitable dispersing or suspending agent, a buffer, and a preservative have been added or suspensions inpeanut oil or sesame oil that have been gelled by theaddition of 2% aluminum monostearate. Some commercialproducts are mixtures of penicillin G potassium or sodiumwith penicillin G procaine; the water-soluble salt providesrapid development of a high plasma concentration of penicillin,and the insoluble salt prolongs the duration of effect.
|