The proposed DSM-IV criteria for substance use disorders have included, as an option, a subtyping for physiologic dependence, characterized by either tolerance or withdrawal. Even if this option is not chosen at this stage of system revision, this weighting scheme justifies wider surveillance of these symptoms, especially for the more newly described cocaine dependence disorder. Wider surveillance of withdrawal is possible with the CIDI Substance Abuse Module (SAM), a WHO/ADAMHA diagnostic interview which covers criteria of substance use disorders according to the DSM-III, III-R, ICD-10 and proposed DSM-IV systems. To aid in this effort, we used the SAM, which includes a master list of all symptoms (n = 16) in the DSM manuals related to withdrawal from any substance to assess withdrawal symptoms from all substances. In this study, we hypothesized that the persons who used opiates with cocaine might misattribute their symptoms to cocaine; thus, we compared the responses of persons who used cocaine and opiates (opiate users) with the responses of persons who used cocaine without opiates (non-opiate users). Data from two St. Louis studies were combined for these analyses, users not in treatment or newly enrolled to drug-free or methadone treatment from a NIDA demonstration project and users selected for the St. Louis DSM-IV Field Trial. Of the 196 persons included from the field trial, 80% reported lifetime cocaine use compared with 91% of the 412 persons from the demonstration project. The symptoms mentioned in the diagnostic manuals were among the most frequently endorsed by both cocaine use groups.(ABSTRACT TRUNCATED AT 250 WORDS)