RecruitingEarly Phase 1Drug trialPK/PD of Oral and Vaporized Delta-9-Tetrahydrocannabinol (THC) in Older AdultsThe overarching goal of this double-blind, placebo-controlled, crossover study is to characterize the pharmacokinetic (PK) and pharmacodynamic (PD) effects of the main analgesic and psychoactive constituent of cannabis, delta-9 tetrahydrocannabinol (THC), among older adults - the fastest growing population of cannabis consumers, and the most likely age cohort to use cannabinoids to relieve pain. This protocol includes two sub-studies, each randomizing 20 men and women aged 65 years or older to receive two administration routes of THC; oral administration and vaporized administration.