Pyridoxine, vitamin B6, is also supposed to reduce leg cramps. Taurine, an amino acid in meat, can have an effect in the treatment of leg cramps. It is often used in combination with glutamic acid and aspartic acid. DL-Phenylalanine is supposed to dampen the pain when cramping. Peppermint has a weak action but can anyhow lessen cramps.
Doctors often prescribe quinine.
Quinine raises the treshold for acetylcholine at the motor end plate. Quinine sulfate 300 mg orally. Some doctors have prescribed diazepam, carbamazepine or diphenhydramine. Some even prescribe phenytoin 0.3-0.6 g daily during the day if the patient have leg cramps at daytime. To my knowledge leg cramps isn't an indication for phenytoin.