Lance R. McMahon, Ph.D., M.S.

Lance R. McMahon

Chair and Professor



PHONE: 352-294-8878

CV: Link to CV



  • Ph.D. Psychology Texas A&M University
  • M.S. Psychology Texas A&M University
  • B.A. Psychology University of Pennsylvania

Research Interests

Research in my laboratory integrates principles of behavior and receptor theory to identify central nervous system mechanisms responsible for drug dependence. We also investigate novel pharmacological strategies that maximize therapeutic potential and minimize abuse and dependence liability. We combine behavioral and physiological approaches, receptor-selective ligands, and quantitative analyses of drug interactions. We are interested in several pharmacological classes of abused drugs.

  • Cannabinoids, for example, include cannabis-derived tetrahydrocannabinols, numerous synthetic cannabinoids, and endogenous cannabinoid neurotransmitters. We systematically compare the effects of cannabinoids and evaluate underlying receptor mechanisms to better understand dependence and therapeutic potential.
  • Cholinergic drugs of interest include FDA-approved smoking cessation aids such as nicotine, varenicline, and bupropion. We compare the effects of smoking cessation aids and investigational nicotinic acetylcholine receptor drugs to better understand relationships between nicotinic acetylcholine receptor subtypes, intrinsic activity (i.e., efficacy), and behavioral effects.
  • Most recently, we are joining investigators in the Departments of Medicinal Chemistry (McCurdy), Pharmaceutics (Avery), and Pharmacodynamics (McLaughlin, Peris) to evaluate the in vitro and in vivo pharmacology of kratom and its derivatives which have proven therapeutic utility in the reduction of opioid dependence.

Select Publications

Hruba L, McMahon LR. Apparent affinity estimates and reversal of the effects of synthetic cannabinoids AM-2201, CP-47,497, JWH-122, and JWH-250 by rimonabant in rhesus monkeys. J Pharmacol Exp Ther 2017 Aug;362(2):278-286.

De Moura FB, McMahon LR. The contribution of α4β2 and non-α4β2 nicotinic acetylcholine receptors to the discriminative stimulus effects of nicotine and varenicline in mice. Psychopharmacology (Berl) 2017 Mar;234(5):781-792.

Moerke MJ, Zhu AZ, Tyndale RF, Javors MA, McMahon LR. The discriminative stimulus effects of i.v. nicotine in rhesus monkeys: Pharmacokinetics and apparent pA2 analysis with dihydro-β-erythroidine. Neuropharmacology 2016 Dec;116:9-17.

Cunningham CS, Moerke MJ, Javors MA, Carroll FI, McMahon LR. Attenuated nicotine-like effects of varenicline but not other nicotinic ACh receptor agonists in monkeys receiving nicotine daily. Br J Pharmacol 2016 Dec;173:3454-3466.

McMahon LR. Enhanced discriminative stimulus effects of Δ9-THC in the presence of cannabidiol and 8-OH-DPAT in rhesus monkeys. Drug Alcohol Depend 2016 Aug;165:87-93.

Moerke MJ, de Moura FB, Koek W, McMahon LR. Effects of nicotine in combination with drugs described as positive allosteric nicotinic acetylcholine receptor modulators in vitro: discriminative stimulus and hypothermic effects in mice. Eur J Pharmacol 2016 May;786:169-178.