Enhancement of cocaine's abuse liability
in methadone maintenance patients

Preston KL, Sullivan JT, Strain EC, Bigelow GE
NIDA Division of Intramural Research,
Baltimore, MD 21224, USA.
Psychopharmacology (Berl) 1996 Jan;123(1):15-25


The present study was conducted to determine whether methadone maintenance alters the pharmacodynamic effects of single doses of cocaine. Twenty-two current users of IV cocaine who were not seeking treatment for their illicit cocaine use participated while living on a research unit. Eleven were maintained on methadone 50 mg PO daily as treatment for their opioid abuse; 11 were opioid abusers who were not physically dependent on opioids and who provided opioid-free urines throughout the study. Each subject received acute cocaine challenge doses of 0, 12.5, 25, and 50 mg intravenously in random order under double-blind conditions in separate test sessions. Physiologic and subject-rated responses were measured before injection and for 2 h after. In the methadone maintenance group, cocaine challenge sessions occurred 15.5 h after the daily methadone dose. There were significant differences between the methadone-dependent and nondependent groups: 1) baseline differences related to chronic methadone administration and not associated with cocaine administration (lower respiration rates and pupil diameter; higher skin temperature) and 2) differences in response to cocaine administration; cocaine-induced increases in subject ratings of Drug Effect, Rush, Good Effects, Liking, and Desire for Cocaine and in heart rate were greater in the methadone maintenance patients compared to the non-dependent group. These results indicate that the positive subjective effects and some physiological effects of cocaine are enhanced in methadone-maintained individuals, suggesting a pharmacological basis for the high rates of cocaine abuse among methadone maintenance patients.
Intravenous rush
LAAM v methadone
Does tapering work?
Methadone in the UK
Opioids and depression
Methadone plus cocaine
Methadone and cancer pain
Methadone: "killer drug" etc
Buprenorphine v methadone
Methadone for tramadol addicts?
Methadone maintenance/subliminal euphoria

and further reading

Future Opioids
BLTC Research
Utopian Surgery?
The Abolitionist Project
The Hedonistic Imperative
The Reproductive Revolution
Critique of Huxley's Brave New World

The Good Drug Guide
The Good Drug Guide

The Responsible Parent's Guide
To Healthy Mood Boosters For All The Family