indication

Nonoxynol 9 is a surfactant spermicide used for contraception in spermicidal creams, jellies, foams, gel, and lubricants. It is also used in conjuction with other methods of contraception, including condoms, cervical caps and diaphragms.

mechanism of action

Nonoxynol-9 interacts with the lipids in the membranes of the acrosome and the midpiece of the sperm. The sperm membranes are lysed; the acrosome, neck and midpiece of the spermatozoa are loosened and then detached which results in their immobilization and death.

toxicity

The major drawback of nonoxynol-9 is its detergent-type action on epithelial cells and the normal vaginal flora. Detergent-type spermicides alter the vaginal flora, possibly leading to an increased risk of opportunistic infections. These are known to enhance the susceptibility of the epithelium of the lower genital tract to HIV and human papillomavirus infection. N-9 can cause vaginal irritation and allergic vaginitis as well as genital irritation in male partners.