Summary

Catatonia is a motor and behavioural syndrome with multiple psychiatric, general medical and neurological aetiologies that might be simultaneously present. B₁₂ deficiency is a rare, treatable cause of catatonia, not always easy to rule out. The authors present a case of a woman with catatonia associated with severe cyanocobalamin deficiency, admitted to an internal medicine ward. The benign course was related to an adequate and early diagnosis.