In order to investigate the possible interactions of propofol with the
dopaminergic system, a prospective, randomized, double-blind, placebo
-controlled study was performed on the profile of prolactin secretion,
since prolactin blood levels are known to increase when dopaminergic
receptors are blocked. Ten fasting female patients scheduled to receiv
e cancer chemotherapy were allocated to receive either propofol at a r
ate of 1 mg . kg(-1) . h(-1) or Intralipid(R) 0.1 ml . kg(-1) . h(-1).
The study included two consecutive chemotherapy cycles; each patient
received in a random order propofol or Intralipid(R). The infusions we
re started 4 h prior to induction of chemotherapy; prolactin blood lev
els were determined at time 0, 30, 60, 120, and 240 min (end of the st
udy period). The basal prolactin blood levels were 14.2 +/- 4.3 vs 12.
8 +/- 2.7 and 10.7 +/- 1.7 vs 14.0 +/- 3.6 ng/mL at the end of the stu
dy for propofol and Intralipid(R), respectively. These results suggest
that the antiemetic properties of propofol are not mediated via inter
actions with the dopaminergic system.