Creatine monohydrate treatment alleviates muscle cramps associated with haemodialysis.

BACKGROUND Muscle cramp is a common complication of haemodialysis. The exact mechanism of this complication is still unknown. Many approaches have been used to relieve the muscle cramping but have had variable effects. One of the possible mechanisms of haemodialysis-associated muscle cramps (HAMC) is the disturbance of muscle energy metabolism. Creatine monohydrate can enhance muscle metabolism. We evaluated the clinical effect of creatine monohydrate on HAMC. METHODS Ten patients with frequent muscle cramps during haemodialysis were randomly selected into two groups, control and placebo. In a double-blind manner, 12 mg of creatine monohydrate or placebo was given to each patient before each dialysis session for 4 weeks. The incidence of muscle cramp during haemodialysis was compared between the two groups. Dialysis adequacy, haemodynamic status, and side-effects were also evaluated. We continued to observe and compare the patients during a 4-week washout period to verify the effect of creatine monohydrate. RESULTS The frequency of symptomatic muscle cramps decreased by 60% in the creatine monohydrate treatment group (6.2+/-0.8 vs 2.6+/-1.8 times/4 weeks, P<0.05) during the treatment period. This decreasing incidence of muscle cramps disappeared in the washout period in the creatine group (6.6+/-1.1 times/4 weeks). There was no difference in the incidence of muscle cramps in the placebo group. The haematocrit, Kt/V, serum albumin, and haemodynamics remained unchanged in both groups during the treatment and washout periods. Serum creatinine increased slightly after creatine monohydrate treatment (10.7+/-3.2 vs 12.4+/-3.2 mg/dl, P<0.05). No adverse effect was found in either group during the treatment and washout periods. CONCLUSION These data suggest that creatine monohydrate can reduce the incidence of HAMC and that it may be a safe agent.