The diagnosis and treatment of catatonia.

Catatonia is a severe neuropsychiatric syndrome that affects emotion, speech, movement and complex behaviour. It can occur in a wide range of psychiatric and neurological conditions, including depression, mania, schizophrenia, autism, autoimmune encephalitis (particularly NMDAR encephalitis), systemic lupus erythematosus, thyroid disease, epilepsy and medication-induced and -withdrawal states. This concise guideline highlights key recommendations from the British Association for Psychopharmacology (BAP) Catatonia Guideline, published in April 2023. Important investigations may include neuroimaging, electroencephalography and assessment for neuronal autoantibodies in serum and cerebrospinal fluid. First-line treatment comprises benzodiazepines and/or electroconvulsive therapy. The benzodiazepine of choice is lorazepam, which is sometimes used in very high doses. Multidisciplinary working between psychiatrists and physicians is often essential. The main limitation of the guidelines is the low quality of the underlying evidence, comprising mainly small observational studies and case reports or series.