Ibogaine fails to reduce naloxone-precipitated withdrawal in the morphine-dependent rat.

Abstract

Because of anecdotal reports in which ibogaine eliminates opioid withdrawal symptoms in humans, we studied this phenomenon in the rat model. Ibogaine (5, 10, 20 and 40 mg kg-1, s.c.) was administered 15 min before naloxone (0.5 mg kg-1, s.c.) in morphine dependent rats (3 days after the s.c. implantation of a 75 mg morphine pellet). Of the 12 withdrawal signs scored, the only significant changes observed after ibogaine (compared with vehicle control) was a decrease in grooming (10 mg kg-1) and an increase in teeth chatter (5 mg kg-1). In spite of ibogaine's apparent interaction with several neurotransmitter receptor systems, it does not alleviate opioid withdrawal in this animal model at non-tremorigenic (5 and 10 mg kg-1) or tremorigenic (20 and 40 mg kg-1) doses.