The human immunodeficiency virus (HIV) is a lentivirus (a subgroup of retrovirus) that causes the acquired immunodeficiency syndrome (AIDS), a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. Without treatment, average survival time after infection with HIV is estimated to be 9 to 11 years, depending on the HIV subtype. Infection with HIV occurs by the transfer of blood, semen, vaginal fluid, pre-ejaculate, or breast milk. Within these bodily fluids, HIV is present as both free virus particles and virus within infected immune cells.

HIV infects vital cells in the human immune system such as helper T cells (specifically CD4+ T cells), macrophages, and dendritic cells. HIV infection leads to low levels of CD4+ T cells through a number of mechanisms, including apoptosis of uninfected bystander cells, direct viral killing of infected cells, and killing of infected CD4+ T cells by CD8 cytotoxic lymphocytes that recognize infected cells. When CD4+ T cell numbers decline below a critical level, cell-mediated immunity is lost, and the body becomes progressively more susceptible to opportunistic infections.

Medical Marijuana Efficacy

A recent report reported that over 60 percent of patients suffering HIV/Aids identify themselves as “medical cannabis users.” Patients living with HIV/AIDS most frequently report using cannabis to counter symptoms of anxiety, appetite loss and nausea, at least one study done has reported that patients who use cannabis therapeutically are just over 3x more likely to adhere to their antiretroviral therapy regimens than non-cannabis users.

Clinical trial data indicates that cannabis use does not adversely impact CD4 and CD8 T cell counts and may even improve immune function.

Investigators at Columbia University published clinical trial data in 2007 reporting that HIV/AIDS patients who inhaled cannabis four times daily experienced “substantial … increases in food intake … with little evidence of discomfort and no impairment of cognitive performance.” They concluded, “Smoked marijuana … has a clear medical benefit in HIV-positive subjects.”