Neuroleptic malignant syndrome is an uncommon but potentially fatal side effect of antipsychotic drug treatment. Several serious complications have been associated with neuroleptic malignant syndrome, such as acute renal failure, deep venous thrombosis, pulmonary embolism and aspiration pneumonia. Reports on infections other than aspiration pneumonia appear, from the literature, to be uncommon. Four cases of infection (three cases of upper respiratory tract infection and one case of urinary tract infection) which developed during the course of neuroleptic malignant syndrome are reported and pathophysiological mechanisms underlying their presentation are suggested.