Catatonia is an underdiagnosed psychomotor syndrome that can occur in the context of various mental and somatic diseases. Malignant catatonia is particularly relevant in the context of intensive medical care. Clear recommendations in guidelines are missing. To present the current state of the diagnosis and treatment of catatonia, especially malignant catatonia. The literature was evaluated with respect to acute catatonic conditions, with aspecial focus on the differential diagnosis, relevance to intensive medical care and treatment of catatonia. In psychiatric inpatients, catatonic syndromes are relatively frequent with aprevalence between 9% and 17%, and in neurological patients somewhat less frequent with aprevalence of 3.3%. There is aclear recommendation for pharmacological treatment with lorazepam. Additional electroconvulsive therapy (ECT) should be considered as early as possible, especially in cases not responding to benzodiazepines. Response rates to ECT have been shown to be 80-100%. In malignant catatonia, ECT should be performed immediately as an emergency indication. Several factors lead to the underdiagnosis of catatonia. It is problematic that even life-threatening malignant catatonia is often not recognized as such, although there is a mortality of about 50% if untreated. The best treatment outcome is achieved with acombination of benzodiazepines and ECT. The treatment of severe malignant catatonia represents an emergency indication for ECT.