Selected Publications
  • Stewart, J.L.,McMahon, L.R., (2011) The fatty acid amide hydrolase inhibitor URB 597: interactions with anandamide in rhesus monkeys. British Journal of Pharmacology (in press).
  • Singh, H., Schulze D.R.,McMahon, L.R., (2011) Tolerance and cross-tolerance to cannabinoids in mice: schedule-controlled responding and hypothermia. Psychopharmacology 215:665-75.
  • Cunningham, C.S.,McMahon, L.R., (2011) The effects of nicotine, varenicline, and cytisine on schedule-controlled responding in mice: differences in α4β2 nicotinic receptor activation. European Journal of Pharmacology 654:47-52.
  • McMahon, L.R., (2011) Chronic Δ9-tetrahydrocannabinol treatment in rhesus monkeys: differential tolerance and cross-tolerance among cannabinoids. British Journal of Pharmacology 162:1060-73.
  • Javors, M.A., Sanchez, J.J,McMahon, L.R., (2010) Quantification of rimonabant (SR 141716A) in monkey plasma using HPLC with UV detection. Journal of Chromatographic Science 48:491-5.
  • Stewart, J.L.,McMahon, L.R., (2010) Rimonabant-induced Delta9-tetrahydrocannabinol withdrawal in rhesus monkeys: discriminative stimulus effects and other withdrawal signs. Journal of Pharmacology and Experimental Therapeutics 334:347-56.
  • Giuffrida, A.,McMahon, L.R., (2009) In vivo pharmacology of endocannabinoids and their metabolic inhibitors: therapeutic implications in Parkinson's disease and abuse liability. Review. Prostaglandins Other Lipid Mediat 91(3-4):90-103.
  • Beardsley, P.M., Thomas, B.F.,McMahon, L.R., (2009) Cannabinoid CB1 receptor antagonists as potential pharmacotherapies for drug abuse disorders. Review. International Review of Psychiatry 21:134-42.
  • Gerak, L.R.,McMahon, L.R., (2008) Acute cross tolerance to midazolam, and not pentobarbital and pregnanolone, after a single dose of chlordiazepoxide in monkeys discriminating midazolam. Behavioural Pharmacology 19:796-804.
  • McMahon, L.R., Li JX, Carroll FI, France CP (2008) Some effects of dopamine transporter and receptor ligands on discriminative stimulus, physiologic, and directly observable indices of opioid withdrawal in rhesus monkeys. Psychopharmacology (in press).
  • McMahon, L.R., (2008) Apparent affinity estimates of rimonabant in combination with anandamide and chemical analogs of anandamide in rhesus monkeys discriminating Δ9-tetrahydrocannabinol. Psychopharmacology (in press).
  • Li JX, McMahon LR, Gerak LR, Becker GL, France CP (2008) Interactions between Δ9-tetrahydrocannabinol and mu opioid receptor agonists in rhesus monkeys: discrimination and antinociception. Psychopharmacology (in press).
  • Li JX, McMahon, LR, France CP (2008) Comparison of naltrexone, 6alpha-naltrexol, and 6beta-naltrexol in morphine-dependent and in nondependent rhesus monkeys. Psychopharmacology 195:479-86.
Lance McMahon

Lance McMahon

Associate Professor of Pharmacology
Ph.D., Texas A&M University

Office: 210-567-0143


View video introduction to Dr. McMahon's lab



drug dependence, cannabinoids, nicotine, opiods, sedative-hypnotics, behavior


Research Summary

Drug dependence can have devastating consequences not only for the dependent individual, but also for family, friends, public health, and society. Developing effective therapies for drug dependence requires an understanding of the environmental, behavioral, and pharmacologic determinants responsible for drug use. Research in my laboratory integrates principles of behavior and receptor theory to identify mechanisms in the nervous system responsible for the abuse liability of sedative-hypnotics, opioids, and cannabinoids.


Cannabis use, in particular, has received considerable scrutiny. From the perspective of public health, cannabis appears to have some therapeutic value on the one hand and deleterious effects on performance and quality of life on the other. Current research emphasizes:


1) Mechanism(s) of cannabinoid action. The effects of cannabis that lead to its self-administration are hypothesized to be mediated by a common mechanism at a particular cannabinoid receptor subtype. Results of ongoing studies suggest that a single mechanism does not account for the behavioral effects of cannabinoids.


2) Dependence that results from chronic cannabinoid treatment. Learned behavior is being used to better understand the neuropharmacology of cannabis dependence, as defined by withdrawal upon discontinuation of cannabinoid treatment, and to identify medicines that might alleviate withdrawal in those seeking to achieve abstinence in the clinic.

• Lectures, Posters and Presentations •

'Effects of the cannabinoid JWH-018, a primary component of K2/Spice, in rhesus monkeys', The College on Problems of Drug Dependence, Miami, FL., June 19, 2011

• Lab Personnel •

Megan Jo 'MJ' Moerke - Graduate Student

Fernando Moura - Graduate Student