Extrapyramidal symptoms related to adjunctive nizatidine therapy in an adolescent receiving quetiapine and paroxetine.

Weight gain is a serious problem with recently introduced atypical antipsychotic agents. Nizatidine, a histamine2 (H2)-receptor antagonist, may help reduce this weight gain. To our knowledge, no adverse effects have been reported when nizatidine is given at recommended doses with atypical antipyschotic agents. We describe, however, an adolescent who was receiving quetiapine and paroxetine for schizophrenia and depression, and developed extrapyramidal symptoms (EPS; parkinsonism and akathisia) after taking nizatidine for weight loss. Based on a report of another patient who developed EPS after taking higher-than-recommended doses of nizatidine, we reviewed the literature on treatment with H2-receptor antagonists for weight gain and on central nervous system adverse effects of nizatidine. Nizatidine may be effective for reducing weight gain associated with both medical and psychiatric conditions. Its safety profile is usually benign, although some patients may develop serious adverse effects, such as EPS and delirium. Therefore, the drug is recommended for short-term management of weight gain associated with atypical antipsychotic agents. Patients receiving nizatidine therapy should be monitored closely for development of EPS, particularly when high doses are prescribed.