Conclusions and relevance: D-cycloserine is associated with a small augmentation effect on exposure-based therapy.

We suggest this occurs by ring opening of the cycloserine ring followed by decarboxylation.

Patients receiving 15 mg of cycloserine improved significantly on one section of an implicit memory test.

Beta-chloro-L-alanine and L-cycloserine were found to generate characteristic PLP-adducts that produced inactivation of SPT in an irreversible manner.

Cycloserine was well tolerated but did not demonstrate consistent evidence of efficacy during the course of therapy.

D-Cycloserine participants gained 3 pounds relative to 0.5 pounds in the placebo group.