Tetrahydrocannabinol (THC) was first isolated from
hemp in 1965. THC's
intoxicating and
medicinal properties have been touted for thousands of years; however, use of the substance is highly controlled in the U.S. and in some other countries.
Delta-trans-tetrahydrocannabinol, in capsule form more commonly known as dronabinol and sold as Marinol by Roxane Laboratories, is federally recognized as an appetite stimulant and anti-nausea/vomiting (antiemetic) agent (though some research indicates it is useful as an anti-glaucoma agent as well). It is available only through special prescription to treat persons suffering from chemotherapy- or radiation-related nausea, and to treat people suffering from AIDS-related anorexia. The FDA approved it for use as an antiemetic for chemotherapy patients in 1985 and as an appetite stimulant for AIDS patients in 1992.
Dronabinol has a complicated effect on the central nervous system, but it basically suppresses the neural impulses associated with nausea and stimulates the appetite (sometimes quite dramatically). As an appetite stimulant, a typical effective dose is 5 milligrams/day (2.5 mg an hour before lunch and dinner), though in clinical trials the dose ranged from 2.5-20 mg/day. As an antiemetic, total daily dosages range from 2.5-40 mg/day. Antiemetic doses are administered every four to six hours and seem to work best for people undergoing chemotherapy for lymphoma.
Side effects of dronabinol can include sleepiness, dizziness, confusion, and rapid heartbeat. Extreme overdoses can cause panic attacks, seizures in epileptics, and possibly hallucinations. Long-term use can possibly result in psychological addiction. Abrupt discontinuation of the drug can cause symptoms such as irritability, insomnia and sweating. In animal studies, dronabinol caused stillbirths and pup mortality, so it's recommended that pregnant women avoid the drug.
References:
Budavari, Susan, ed. 1989. The Merck Index: An Encyclopedia of Chemicals, Drugs and Biologicals. Rahway, NJ, Merck & Co.
Simpson, Beryl Brintnall and Molly Conner-Ogorzaly. 1986. Economic
Botany: Plants in Our World. New York, NY, McGraw-Hill Publishing
Co.
1995 Physician's Desk Reference ©. Montvale, NJ, Medical
Economics Data Production Company.