Creatine for amyotrophic lateral sclerosis/motor neuron disease.

Creatine, a naturally-occurring nitrogenous organic acid involved in adenosine triphosphate (ATP) production, has been shown to increase survival in mouse models of amyotrophic lateral sclerosis (ALS). Results from human trials, however, have been mixed. Given conflicting results regarding creatine's efficacy, we conducted a systematic review.