Clinical Uses of Marijuana

2009.04.26

The medical uses of marijuana have spread worldwide. It has been used for medicinal purposes for twelve years now. In the year 1997, the National Institutes of Health distributed a report detailing the possible medical uses for marijuana. The reports high lightened five areas of medical care that were most appropriates and these includes the stimulation of appetite and alleviate cachexia, control nausea and vomiting associated with cancer chemotherapy, decrease intraocular pressure, analgesia and neurological and movement disorders.

Marijuana is believed to increase appetite and food intake after smoking. In 1970’s, surveys showed that 93 percent of marijuana users reported enjoying food and subsequently ate more after smoking. It has been shown to increase appetite and weight gain in HIV infected patients. Studies performed regarding dronabinol's antiemetic effects. It showed that dronabinol’s was superior to placebo in nausea caused by chemotherapy that induced a moderate amount of emesis.

Numerous studies documented the affect of marijuana on pain.  It yield mixed results but the overall consensus is that marijuana does have some analgesic properties. On several animal studies using rats and mice conclude that delta-9-THC is equipotent and possible even more potent than morphine in controlling pain. The Medical Utility of marijuana concluded that THC has some analgesic effect on humans. There is a very narrow therapeutic window between effective analgesia and neurological adverse effects. However, the use of delta-9-THC is limited in most kinds of pain. They admitted that the control of neurogenic pain is lacking and the role of THC takes place.

In neurological and movement disorders, there are reports that marijuana has antispasmatic, antitremor, and antiataxic activity. In nosocomial or clinical setting, both smoked and oral marijuana have been used in Parkinson's disease and Huntington's chorea. It also relieves spasticity and nocturnal spasm associated with multiple sclerosis and spinal cord injuries.

In 1976, studies found out that marijuana cigarettes with 4% THC lowered intraocular pressure by as much as 27 percent when compared to placebo. Oral dosages of THC lowered intraocular pressure by 17% when compared to placebo.  Studies noted that marijuana was particularly effective in those with refractory glaucoma. However, even though there are evidences that marijuana lowers intraocular pressure, there are no conclusive no conclusive studies indicate that the components of marijuana can safely and effectively lower intraocular pressure enough to prevent optic nerve damage. 

Marijuana active ingredients most especially the cannabinoids were shown to inhibit tumor angiogenesis in mice. It works by increasing the potency of a fat molecule known as ceramide.  Increased ceramide activity inhibits cells that would normally produce VEGF and encourage blood vessel growth. Changes in the pathway were paralleled by changes in tumor size. Moreover, intratumoral administration of the cannabinoid Delta9-tetrahydrocannabinol to two patients with glioblastoma decreased VEGF levels and VEGF receptor activation in the tumors. Barrier of the VEGF pathway constitutes one of the most promising antitumoral approaches currently available. Recent findings provide a novel pharmacological target for cannabinoid-based therapies.