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.