Only one study involving 62 patients examined the effects of cannabinoids on immune function and parameters associated with HIV infection. Participants in this study were assigned to either a 3.95% THC marijuana cigarette, a 2.5 mg dronabinol capsule or a place capsule three times per day for 21 days. For the marijuana group, there was a statistically significant increase in CD4 counts from baseline versus placebo, and for the dronabinol group, there was a trend towards statistical significance. Neither CD4 nor CD8 cell counts were adversely affected, and the pharmacokinetic component of the study did not reveal any clinically significant interactions that would require dose adjustments of protease inhibitors (PIs). Adverse effects across studies included concentration difficulties, fatigue, sleepiness or sedation, increased duration of sleep, reduced salivation and thirst that improved on discontinuation. The authors of a systematic review on the use of cannabis for reducing morbidity and mortality in HIV concluded that: (1) evidence for substantial effects on morbidity and mortality is currently limited and (2) evidence for safety and efficacy of cannabis is lacking. Studies have been of short duration, in small numbers of patients and have focused on short-term measures of efficacy. Furthermore, no study examined the effects of cannabinoids on inflammatory markers or HIV reservoir markers through a randomised trial.