Adjunctive Glycine for Obsessive Compulsive Disorder

Individuals with obsessive compulsive disorder (OCD) often find inadequate relief, even with
the best of currently available treatments. Some evidence suggests the the neurotransmitter
glutamate may be a useful target for new treatments for OCD. The amino acid glycine, if
given orally in adequate dosages, can have specific effects on one particular glutamate
receptor molecule in the brain, that might be helpful with OC symptoms. This randomized,
double-blind protocol will have study participants who suffer with OCD take either a glycine
preparation or placebo for 12 weeks. Clinical measures (e.g., Y-BOCS, NIMH-OC) will be
recorded at each visit to determine whether those taking the glycine experience clinical
benefit.

Inclusion Criteria:

- Diagnosis of OCD present for at least 1 year

- Male or female, age 18 to 65

- Stable medication regimen for 12 weeks prior to study entry

- at least moderately severe OC symptoms

Exclusion Criteria:

- Active substance use disorder within the last 6 months

- Comorbid schizophrenia, schizoaffective disorder, bipolar disorder, tic disorder,
Tourette Disorder, schizotypal personality disorder

- Hoarding as the principal OCD symptom

- Insulin-dependent diabetes mellitus

- Pregnant or breastfeeding