Neuroleptic malignant syndrome associated with amisulpride and lithium: a case report

Neuroleptic malignant syndrome (NMS) is a rare and potentially lethal complication of antipsychotic medication. We have found in the literature six case reports of NMS associated with amisulpride, however in three of them concomitant factors played a probable role. We present a case of NMS, which appeared 10 days after addition of amislupride to ongoing lithium and valproic acid therapy in a patient with bipolar disorder. The onset of NMS was preceded by symptoms of lithium toxicity. Total resolution of all NMS symptoms was achieved 23 days after discontinuation of lithium and amisulpride. Nevertheless, 36 days later, after 20 days of medication with quetiapine added to valproic acid, there occurred elevation of serum creatine kinase (CK) and myoglobin levels with no prior clinical manifestation of NMS. The case indicates the increased risk of NMS due to amisulpride added to lithium. The susceptibility to NMS is present even after symptoms resolution. For that reason, the serum CK and myoglobin levels should be controlled if antipsychotic medication is implemented in patients with past history of NMS although clinical symptoms of NMS are absent.