Slight sedation was observed in 9 patients (4.5%) as a side-effect. Other marked side-effects or adverse events were absent. Compared to placebo, there was a trend toward lower mortality in the 2.0 g/day glycine group and a significant decrease in mortality in the 1.0 g/day group (p < 0.05). A significant decrease in the number of patients with severe disability was found in the 1.0 g/day glycine group (p < 0.01 vs. placebo; p < 0.05 vs. 0.5 g/day glycine) and in the 2.0 g/day glycine group (p < 0.05 vs. placebo; p < 0.05 vs. 0.5 g/day glycine). Both the 1.0 and 2.0 g/day glycine groups showed a significant improvement on the OSS (p< 0.01) and the SSS (p < 0.01) while there was a trend toward improvement on these measures in the placebo group and the 0.5 g/day glycine group.