Medicinal Cannabis for Painful HIV Neuropathy

Inclusion Criteria: * Documented HIV infection * Meets clinical and electrodiagnostic criteria for HIV-associated DSPN at entry * Daily pain for at least three consecutive months with an average daily pain magnitude score of at least 5 on the Descriptor Differential Scale * Inadequate pain relief with prior treatment for painful HIV neuropathy using drugs from at least two different classes of pain-modifying agents (NSAIDS, low-potency opioids, high-potency opioids, sodium channel blockers, other adjunctive pain treatments) * Age 21-65 years * Stable use of opioid and non-opioid analgesic medications during the two weeks prior to study entry Exclusion Criteria: * Positive urine toxicology screen for cannabinoids during the "wash-in" week prior to initiating study treatment * Recent (i.e. during the month prior to study entry) history of marijuana use more than twice a week * Previous psychosis with or intolerance to cannabinoids * A lifetime history (ever) of dependence on cannabis * Meeting criteria for alcohol or drug dependence within the last 12 months * Active, major psychiatric disorder likely, in the investigator's opinion, to interfere with adherence to the study protocol * Active AIDS-defining opportunistic disease (a history of AIDS-defining opportunistic disease which is no longer active or progressing will not be grounds for exclusion) * Diabetes mellitus, renal failure with uremia, alcohol abuse, previous spinal surgery, or other documented causes of neuropathy or neuropathic pain * Pulmonary disease of sufficient severity to require the use of supplemental oxygen * Asthma * Life expectancy less than 6 weeks or an active, acute illness likely to interfere with completion of the study protocol * Pregnancy * Failure to use adequate birth control in an individual with reproductive potential * Minority status (less than 21 years), or persons over age 65 years