Conditions: Obsessive-Compulsive Disorder
Keywords: obsessive-compulsive disorder OCD glutamate N-Acetylcysteine augmentation
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 10
Healthy volunteers: no

Brief summary:
Obsessive-compulsive disorder (OCD) affects 2-3% of the population and leads to a great deal of suffering. Many patients benefit from established treatments, the mainstay of which are cognitive behavioral therapy and a group of antidepressant medications known as serotonin reuptake inhibitors. However, 20-30% of patients get minimal benefit from these established therapeutic strategies. New avenues of treatment are urgently needed.

Existing medications for obsessive-compulsive disorder affect the neurotransmitters serotonin or dopamine; but increasing evidence suggests that functional disruptions of a different neurotransmitter, glutamate, may contribute to some cases of OCD. The researchers are therefore interested in using medications that target glutamate as novel treatment options for those OCD patients who do not benefit from established treatments.

One such medication is the drug N-Acetylcysteine, whose glutamatergic antagonistic properties may be effective in reducing the glutamatergic hyperactivity that is thought to contribute to the pathophysiology of OCD and major depressive disorder (MDD).

Riluzole, which is FDA approved for amyotrophic lateral sclerosis (ALS, or Lou Gehrig's disease) is also a glutamatergic agent. There is evidence that riluzole possesses anti-depressant, anti-obsessional, and anti-anxiety properties.

The modulation of glutamatergic activity is a promising new approach to the treatment of mood disorders. The researchers are therefore now recruiting patients to participate in a double-blind, placebo-controlled trial of N-Acetylcysteine, added to whatever other OCD medications they are taking.

Detailed description:
Due to limited participation, this study has closed.

Arms:
arm 1: Patients randomized to this arm will receive N-Acetylcysteine augmentation, at a standard dose titrated to 3000 mg within the first week, in addition to the medication regimen they are on at enrollment arm 2: Patients randomized to this arm will receive placebo, formulated to be indistinguishable from N-Acetylcysteine, in addition to the medication regimen they are on at study enrollment.

Interventions: intervention 1: N-Acetylcysteine intervention 2: placebo
Intervention descriptions: intervention 1: 3000 mg by mouth PO (1200 mg AM, 1800 mg PM), 12 weeks intervention 2: placebo, 2 capsules PO AM, 3 capsules PO PM, 12 weeks

Protocol document: