Mildly elevated liver function tests can be pr esent in cocaine injectors or users with con-
comitant alcohol use. There are no neurobiological markers of diagnostic utility. Discon-
tinuation of chronic cocaine use may be asso ciated with electroencephalographic changes,
suggesting persistent abnormalit ies; alterations in secretion patterns of prolactin; and
downregulation of dopamine receptors.
Short-half-life amphetamine-type stim ulants (MDMA [3,4-methylenedioxy- N-methyl-
amphetamine], methamphetamine) can be detected  for 1–3 days, and possibly up to 4 days