Abbreviated to d9 THC, this chemical is the most active ingredient in cannabis. A synthetic but molecularly identical version of d9 THC is called dronabinol, and the cannabis plant it self can referred to as hemp or Indian hemp, marijuana, pot, ganja, hashish, and reefer on the streets.

THC is in the news currently as debate proceeds about its reclassification as a class C drug in Britain. Reclassification was deemed necessary as focus on class A drugs becomes more intense. Cannabis will be reclassified as a class C drug by July of 2003, putting it in ranks with steroids and antidepressants.

Tetra hydro cannabinol is an appetite stimulant and antiemetic. A brown, amorphous, viscous oil at standard temperature and pressure.

As the laws prohibiting recreational cannabis use are loosened, funding has been in turn increased for research of the THC compound and its potential benefit to medicine. Already, in some countries, d9 THC is being used in medicine for multiple causes:

1. As an antiemetic to control nausea and vomiting associated with cancer chemotherapy.
2. As an antiemetic to control nausea and vomiting associated with the use of drugs for controlling the spread of the AIDS virus; without which patients could regurgitate the nausea inducing drugs before being properly absorbed by the body.
3. To retard or reverse the weight reduction syndrome of AIDS.
4. To control seizures in patients suffering from epilepsy.
5. To reduce pressure within the eyes associated with glaucoma.
6. To alleviate muscle spasms associated with multiple sclerosis.
7. To alleviate pain and muscle spasms for paraplegics and quadriplegics.

Formal Chemical Name (IUPAC)
(6aR-trans)-6a,7,8,10a- tetrahy- dro6,6,9- trimethyl-3-pentyl-6H- dibenzo[b,d]pyran-1-ol