According to a 2007 study at

The National Cancer Institute reports that THC–the active ingredient in marijuana–may decrease symptoms of nausea or vomiting

Research done by the Scripps Research Institute in California shows that the active ingredient in marijuana, THC, prevents the formation of deposits in the brain associated with Alzheimer’s disease.

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.

A study by Complutense University of Madrid found the chemicals in marijuana promotes the death of brain cancer cells by essentially helping them feed upon themselves in a process called autophagy.

February 2010 investigators at the University of California Center for Medicinal Cannabis Research publicly announced the findings of a series of clinical trials on the medical utility of inhaled cannabis. The studies concluded that marijuana ought to be a “first line treatment” for patients with neuropathy and other serious illnesses.

Another study conducted by the University of California Center for Medicinal Cannabis Research assessed the use of marijuana as a treatment for patients suffering from multiple sclerosis. That study determined that “smoked cannabis was superior to placebo in reducing spasticity and pain in patients with MS, and provided some benefit beyond currently prescribed treatments.”

Investigators at Germany’s Medical School of Hanover, Department of Clinical Psychiatry and Psychotherapy, reported successful treatment of Tourette’s syndrome with a single dose of 10 mg of delta-9-THC.

In January 2006, investigators at the British Royal National Hospital for Rheumatic Disease reported successful treatment of arthritis with cannabinoids researchers at Wroclaw, Poland’s University of Medicine, Department of Dermatology, reported that application of an endocannabinoid-based topical cream reduced uremic pruritus and xerosis.

University of California at San Diego reported in 2008 that inhaled cannabis significantly reduced objective measures of pain intensity and spasticity in patients with MS.

Investigators at the Netherland’s Vrije University Medical Center, Department of Neurology reported in 2003 that the administration of oral THC can boost immune function in patients with MS.

Recently, an international team of researchers from the United States, Switzerland and Israel reported in the Journal of the American College of Cardiology that the administration of CBD reduces various symptoms of diabetic cardiomyopathy
investigators at Germany’s University of Heidelberg evaluated the analgesic effects of oral THC in patients with fibromyalgia. Subjects in the trial THC all reported a significant reduction in daily recorded pain.

Writing in the March 2004 issue of the journal Amyotrophic Lateral Sclerosis & Other Motor Neuron Disorders, investigators at the California Pacific Medical Center in San Francisco reported that the administration of THC both before and after the onset of ALS symptoms staved disease progression.

An observational study by investigators at the University of California at San Francisco (UCSF) found that hepatitis C patients who used cannabis were significantly more likely to adhere to their treatment regimen than patients who didn’t use it.

Italian investigators at the University of Milan, Department of Pharmacology, Chemotherapy and Toxicology, reported that the non-psychoactive cannabinoid, cannabidiol (CBD), inhibited the growth of various human glioma cell lines.