Tryptophan supplementation for nocturnal bruxism: report of negative results.

This experiment was designed to study the effect of L-tryptophan on nocturnal bruxism. Portable EMG recorders were used to monitor unilateral masseter muscle activity during sleep in eight patients identified as nocturnal bruxists. Following an initial baseline period, the patients were given, in a randomized double-blind study, either tryptophan (50 mg/kg of body weight) or a placebo for 8 days followed by an additional 8 days of reverse medication. Dietary patterns and food intake were monitored throughout the experimental period. No significant treatment differences in bruxing levels were found, suggesting that L-tryptophan supplementation in the absence of dietary manipulation is ineffective in the treatment of nocturnal bruxism.