1. Chlorpromazine has many undesirable effects, most of which are transient and of relatively minor clinical significance.2. Complications of greater severity occur in a significant number of cases but generally resolve rapidly and without residuals.3. Four categories of complications are distinguishable: direct or indirect action on various levels of the nervous System, allergic-type reactions, responses of indefinite origin, and indirect effects of drug action.4. Despite its numerous undesirable effects chlorpromazine is clinically a relatively safe drug.