The purpose of this two part study was to better characterize
cocaine users based on self-reported
cocaine withdrawal symptoms by examining screening data and response to smoked
cocaine in the human laboratory. The first study sample included male and female non-treatment seeking
cocaine users who were screened as potential subjects for inpatient studies. Of the 555 subjects, 462 (82%) endorsed symptoms consistent with DSM-IV criteria for
cocaine withdrawal.
Cocaine users who met criteria for
cocaine withdrawal, compared with those who did not, reported a significantly higher amount of
cocaine use and a history of medical and psychosocial problems.
Cocaine users meeting DSM-IV withdrawal criteria, which included endorsement of depression, were also more likely to have a history of depression, to have seriously considered suicide, and to have had chemical dependency treatment even when amount spent on
cocaine was covaried. The second study sample, which was a subset of Study I, included those who participated in human
cocaine studies following the phone screening.
Cocaine users who met criteria for
cocaine withdrawal (n=34), compared with those who did not (n=10), had enhanced subjective ratings of 'high' and 'feel the effect of last dose' in response to a single delivery of 0.4 mg/kg of smoked
cocaine. These results suggest that history of
cocaine withdrawal symptoms may be associated with enhanced
cocaine responses and greater severity of
cocaine dependence.