Effectiveness of quetiapine for poststroke pathological laughing: case report and review of the literature.

Pathological laughing (PL) is an uncommon distressing symptom that occurs in patients with various neurological disorders. Dysregulation of serotonergic system has been proposed as one of the possible mechanisms resulting in this condition, and selective serotonin reuptake inhibitors have been used for treatment of PL with variable effects. However, the pathogenetic mechanism of PL remains largely elusive, and other treatment choices needs to be explored. This case report illustrates the beneficial effect of quetiapine, an atypical antipsychotic agent with enhancing serotonergic neurotransmitter activity, in a patient with post-stroke PL. In addition, previously reported post-stroke PL cases searched from PubMed (1993-2010) were also reviewed. In this report, we demonstrate a 42-year-old man who developed PL 4 weeks after a hemorrhage stroke affecting the paramedian pons. He was treated with dextromethorphan initially but did not show obvious response. Then, the medication was shifted to quetiapine at a dosage of 25 mg/d. There was a significant and rapid recovery 2 days after quetiapine treatment. Our observations expand the current knowledge of treatment of PL caused by pontine lesions. Further large-scale controlled trials are warranted to evaluate the beneficial and differential effects of quetiapine on PL.