People with HIV can use marijuana to stimulate appetite and to reduce nausea.

Many people with HIV have low appetite.
This can be due to fatigue or drug side effects. Marijuana stimulates the appetite, preventing these problems.

Some people with HIV get nauseated when they take antiretroviral medications (ARVs).
This can make it difficult to take all scheduled doses. Marijuana can help control the nausea.
It may also relieve the pain of peripheral neuropathy and is being studied for that purpose.

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Investigators at Columbia University published clinical trial data in 2007 showing 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 that smoked marijuana has a clear medical benefit in HIV-positive patients.

In another study in 2008, researchers at the University of California, San Diego School of Medicine found that marijuana significantly reduces HIV-related neuropathic pain when added to a patient's already-prescribed pain management regimen and may be an "effective option for pain relief" in those whose pain is not controlled with current medications.

Mood disturbance, physical disability, and quality of life all improved significantly during study treatment.
Despite management with opioids and other pain modifying therapies, neuropathic pain continues to reduce the quality of
life and daily functioning in HIV-infected individuals. Cannabinoid receptors in the central and peripheral nervous systems
have been shown to modulate pain perception.

No serious adverse effects were reported, according to the study published by the American Academy of Neurology.