Drug Self-Administration

Procedures for assessing self-administration of' i.v. cocaine have
been reported by Fischman and Schuster (1982) with experienced
cocaine users prepared with two indwelling Angiocath Teflon
catheters, one for drug infusion and one for blood withdrawal.
Subjects were instructed that each of two buttons would be
associated with the same solution (drug or saline) throughout the
study. On the first day, subjects were exposed to each solution and
for the next 8 days were required to press the response button 10
times in order to receive an injection. Once a single response was
made on a given button, the other one was deactivated. A total of
10 injections could be taken during a l-hour session with blood
drawn prior to and after each injection followed by completion of
the POMS and ARC1 questionnaires. After initial sampling on the
first day, subjects consistently chose cocaine over saline.
Subjective ratings of drug effect correlated with the self-injection
of cocaine. The most pronounced effects on subjective states, blood
pressure, heart rate, and cocaine levels occurred after this initial
injection.