A trial of d-cycloserine to treat the social deficit in older adolescents and young adults with autism spectrum disorders.

Autism spectrum disorders are difficult for older adolescents and young adults as impaired social communication affects the transition to adult life. d-Cycloserine, a partial glycine agonist at the N-methyl-d-aspartic acid receptor, was tested in a double-blind randomized trial in 20 older adolescents and young adults with autism spectrum disorders using two dosing strategies (50 mg daily versus 50 mg weekly) for 8 weeks with a 2-week follow-up after discontinuation. d-Cycloserine caused statistically and clinically significant improvement with no differentiation between dosing strategies on the Social Responsiveness Scale and the Aberrant Behavior Checklist before and after d-cycloserine administration.