Neuroleptic-induced catatonia or a mild form of neuroleptic malignant syndrome?

Neuroleptic-induced catatonia (NIC) and milder neuroleptic malignant syndrome (NMS) share parkinsonian features, catatonic symptoms, mild fever, and have been described in patients receiving antipsychotic agents. We report the case of a patient with a schizophreniform disorder and a mild mental retardation who developed a condition which can be diagnosed either as NIC or as a mild form of NMS and has been treated successfully with a combination of amantadine (600 mg/day) and diazepam (30 mg/day). The overlapping between NIC and mild NMS cases might lead to an overestimation of the incidence of current NMS and reinforces the view of the existence of a 'neuroleptic toxicity spectrum'.