We thank Dr Caroff and associates for their careful attention to our article and for the opportunity to clarify several points.Anecdotal reports are generally viewed with considerable caution in medicine. We tried to consider how one might select cases for a prospective study of NMS. If the hypothesis is that neuroleptic drugs are a specific cause, then one would wish to exclude the presence of other factors that could reasonably explain the signs and symptoms. Even in controlled studies subjective judgments are sometimes required, but it is the obligation of the investigator to exclude cases when there is significant doubt. We were surprised to find that only 14 of 67 cases in English-language reports during a specific period of time met this conservative criterion. If this holds true for the many subsequent and foreign-language reports,1 then conclusions based on reviews of such reports might be questioned.
Levinson DF, Simpson GM. Neuroleptic Malignant Syndrome-Reply. Arch Gen Psychiatry. 1987;44(9):839-840. doi:10.1001/archpsyc.1987.01800210091016