The universal field hypothesis of catatonia and neuroleptic malignant syndrome.

Catatonia and neuroleptic malignant syndrome (NMS) are uncommon disorders that can be life-threatening. Many researchers consider them as clinically divergent entities; however, they share similar and overlapping literature on causative agents, phenomenology, and treatment response. This hypothesis considers both disorders as a single entity that result from variable combinations of the following: 1) gamma-aminobutyric acid (GABA) hypoactivity at the GABAA receptor; 2) dopamine hypoactivity at the D2 receptor; 3) serotonin hyperactivity at the 5-HT1A receptor and hypoactivity at the 5-HT2A receptor; and 4) glutamate hypoactivity at the N-methyl-D-aspartate (NDMA) receptor. In this paper, evidence to support this hypothesis is limited to retrospective human studies of catatonia and NMS. The four components of the hypothesis are: 1) GABAA agonists have been shown to alleviate catatonia and NMS; 2) D2 antagonism is proportional to the relative likelihood of NMS and catatonia; 3) 5-HT1A agonism with 5-HT2A antagonism is implicated in catatonia and NMS; 4) NMDA receptor antagonists, such as phencyclidine and ketamine, reduce glutamate transmission. This hypothesis proposes that it is the interaction of these systems that prediposes, initiates, and maintains the twin syndromes of catatonia and NMS.