One third to two thirds of patients with obsessive compulsive disorder (OCD) do not respond adequately to selective serotonin reuptake inhibitors (SSRIs). Augmentation strategies have been tried and are recommended. Antipsychotic augmentation is the most studied, but more recently other strategies were attempted, including the use of medications acting on the glutamatergic system, such as memantine.

The author’s aim is to understand whether there are sufficient evidences for the use of memantine as an adjunctive therapy in OCD.

A literature research was performed, using the following key words: obsessive compulsive disorders, memantine.Retrieved papers were selected according to their relevance for the subject.

Several evidences have pointed to a glutamatergic dysfunction in OCD. Drugs that act on ionotropic receptors or modulate glutamate neurotransmission, such as riluzole, lamotrigine and memantine demonstrated improvements in symptoms when used as adjunctive therapy in refractory OCD.

The use of memantine in OCD has been demonstrated in open-label trials and in two recent randomized controlled trials (RCTs). The RCTs analyzed a total of 82 patients and found a significant improvement in short-term outcomes and higher rates of remission achieved with memantine than placebo, without significantly augmented side effects.

At the present time, there is little evidence to recommend the early use of augmentation strategies. Concerning the memantine’s use, more studies are needed before recommending its use as a routine augmenting agent.