This study took OCD patients that weren’t responding to medication and added a natural treatment, NAC.  They found that it augmented the response to the medications.  Love it when both approaches are used together.

J Clin Psychopharmacol. 2012 Dec;32(6):797-803. doi: 10.1097/JCP.0b013e318272677d.

N-acetylcysteine add-on treatment in refractory obsessive-compulsive disorder: a randomized, double-blind, placebo-controlled trial.