Memantine as an Augmentation Therapy for Anxiety Disorders

Objective . Glutamate, an excitatory neurotransmitter in the central nervous system (CNS), may play a role in the development of anxiety. Memantine partially blocks N-methyl-D-aspartate (NMDA) receptors' glutamate channels located in the CNS. This paper evaluates memantine as an augmentation therapy for treatment of anxiety. Methods . 15 consecutive partially responding anxious patients were treated with adjunctive memantine for 10 weeks. Memantine was dosed 5–20 mg/day. Result . Memantine augmentation resulted in clinically relevant reduction in anxiety symptoms when compared to baseline. Forty percent of patients achieved remission (HAM-A ≥ 7). Memantine improved sleep quality. Mean dose was 14 mg/d (range 5–20 mg/d). Typical adverse events included nausea and headache. Conclusion . The NMDA receptor antagonist memantine may be an effective augmentation therapy in patients with treatment-resistant anxiety.