Spermicide is a form of contraception that uses chemical agents to kill sperm. It's generally inserted into the vagina before intercourse. It's less effective than other forms of contraception and is generally used together with another method, usually a condom.
As a rule, spermicidal preparations are odorless, clear, tasteless, non-staining, and provide lubrication. The usual active chemical is nonoxynol-9. They can be available as gels, foams, or films and are usually available without a prescription.
Typical side effects are local skin irritation.