Gossypol

Scientific Name(S): Gossypol is commonly derived from members of the family Malvaceae. Cotton (Gossypium spp.) represents the most common source.

Gossypol is an herbal medicine used to treat cancer and a female problem called endometriosis. It may also be used by women and men to prevent pregnancy.

History: Gossypol was first identified as an antifertility agent as a result of epidemiologic studies conducted in China during the 1950s. Investigators had been puzzled by the extremely low birth rates in a particular geographic region. The men had very low sperm counts and many women had amenorrhea. Eventually the phenomenon was related to the exclusive use of crude cottonseed oil for cooking. Further investigation revealed that the antifertility component was gossypol, a potentially toxic phenolic pigment found in the seed, stem and root of the cotton plant.

Uses of Gossypol

Gossypol acts as a male and female contraceptive. It may be a treatment for certain gynecological problems and viral infections.

Side Effects of Gossypol

It is potentially toxic. Contraceptive effects may not be reversible.

Dosage: Talk with your caregiver about how much Gossypol you should take. The amount depends on the strength of the medicine and the reason you are taking Gossypol. If you are using this medicine without instructions from your caregiver, follow the directions on the medicine bottle. Do not take more medicine or take it more often than the directions tell you to.

Toxicology: Commercial cotton seed oil is processed in order to remove its gossypol content.

A low incidence of side effects was originally reported in men treated with gossypol. Some men develop a transient weakness during the first days of administration and this appears to be related to hypokalemia induced by gossypol. This may be caused by renal loss of potassium during therapy and can be managed effectively with oral potassium supplementation. Some men notice changes in appetite. Gossypol also inhibits malate dehydrogenase in animals and glutathione-S-transferase in both animals and man. This latter enzyme is involved in the detoxification of potentially toxic and carcinogenic compounds. At high doses (100 to 700 times the contraceptive dose) gossypol may cause diarrhea, hair discoloration, malnutrition, circulatory problems and heart failure. The compound has not been found to be mutagenic when tested in the Ames salmonella microsome test, but questions still remain about is genotoxic characteristics.

The results of more recent well-controlled studies found that the incidence of adverse events was significantly high as to warrant abandoning the development of gossypol as a male contraceptive.

Summary: Gossypol is a toxic component contained in cottonseed. This compound has been shown to be an orally effective male contraceptive. Although it has been used widely in China, its development has not been pursued in the West primarily because its inhibitory effects on spermatogenesis are not predictably reversible. A reduction in dosage may be associated with a lower incidence of permanent sterility. The drug is effective when used as a topical spermicidal cream or gel.