Effect of Cannabis and Endocannabinoids on HIV Neuropathic Pain

Our objective is to assess 120 community-dwelling people living with HIV who have neuropathic pain and are currently using cannabis. These participants will be enrolled in a study that consists of two phases: Phase 1) This will involve a cross over study involving three different doses of vaporized cannabis that contain THC and varying concentrations of CBD: * Low CBD session: 8 puffs of 1.9% THC + 0.01% CBD * Medium CBD sessions: 4 puffs of 1.4% THC + 0.01% CBD plus 4 puffs of 1.4% THC + 5.1% CBD * High CBD sessions: 8 puffs of 1.4% THC + 5.1% CBD This phase will examine the acute effects of cannabis on pain intensity, blood endocannabinoid levels, and the relationship of pain with heart rate variability (HRV). Phase 2) This phase will involve the association between dispensary-obtained cannabis and changes in pain reported via IMPACT, a mHealth text messaging program that will serve as a useful tool to monitor the relationship between pain and cannabis use. Text messaging is an effective method to modify health behaviors, monitor substance use, and track pain. Our group has recently demonstrated the feasibility of using short message service (SMS) texting to promote anti-retroviral therapy adherence and monitor daily methamphetamine (METH) use in persons living with HIV neuropathy with bipolar disorder or METH dependence.