Papaverine hydrochloride is the hydrochloride of an alkaloid obtained from opium or prepared synthetically. It belongs to the benzylisoquinoline group of alkaloids. It does not contain a phenanthrene group as do morphine and codeine.

Papaverine hydrochloride is 6,7-dimethoxy-1-veratrylisoquinoline hydrochloride and contains, on the dried basis, not less than 98.5% of C₂₀H₂₁NO₄•HCI. The molecular weight is 375.85. The structural formula is as shown:

Papaverine hydrochloride occurs as white crystals or white crystalline powder. One gram dissolves in about 30 mL of water and in 120 mL of alcohol. It is soluble in chloroform and practically insoluble in ether.

Papaverine Hydrochloride Injection is a clear, colorless to pale-yellow solution.

Papaverine hydrochloride, for parenteral administration, is a smooth-muscle relaxant that is available in vials containing 30 mg/mL papaverine hydrochloride. Each vial also contains edetate disodium, 0.005%. Sodium hydroxide may have been added during manufacture to adjust the pH.

Last reviewed on RxList: 2/25/2009
This monograph has been modified to include the generic and brand name in many instances.