What You Need to Know About Nonoxynol-9 (N9)

Nonoxynol-9. Photo © 2015 Dawn Stacey

Nonoxynol-9 (N9) Definition:

Nonoxynol-9 (N9) is a chemical detergent and can be found in many common spermicides. It has been used for contraception since the 1950s. Nonoxynol-9 works by damaging sperm cell membranes. By breaking these outer barrier membranes, N9 immobilizes and kills sperm. Once the sperm are destroyed, they are no longer able to fertilize an egg.

Pronunciation: non·ox·y·nol 9 [non-ok´sĭ-nol nīn]


Spermicides that Contain Nonoxynol-9 Can Be Used As:

Warnings and Concern About Nonoxynol-9:

The U.S. Food and Drug Association (FDA) recognizes that nonoxynol-9 has been shown in laboratory studies to be an active against some STD-causing bacteria and viruses by damaging the cell walls of these pathogens. But, the agency is also cautioning people about using this spermicide for that purpose.

  • In 2007, the FDA ordered a labeling change -- manufacturers of over-the-counter spermicide products that contain nonoxynol-9 must include the warning statement that the chemical Nonoxynol-9 (N9) does not provide protection against infection from HIV or other sexually transmitted diseases.

The Official Stance on Nonoxynol-9:

The Centers for Disease Control and Prevention (CDC), the World Health Organization (WHO), and the FDA's official stance on N9 is the following....

  • Nonoxynol-9 is a safe, effective contraceptive option for women who are at low risk for HIV/STDs as long as they do not use N9 more than once a day.

This is based on research that when used frequently or in high dosages, nonoxynol-9 may cause  damage to the cells that line the vagina or cause inflammation of the vagina and/or cervix.

Repeated and/or high-dose use of N9 is also linked to an increased risk of vaginal lesions (abnormal tissue changes) and irritation. This damage and irritation could put you at greater risk for getting HIV, STDs, and urinary tract infections.

Nonoxynol-9 can also irritate cervical mucus, so women who already have HIV should not use N9. This cervical mucus irritation can increase HIV shedding. This makes it easier for a woman to transmit HIV to her partner.

Nonoxynol-9 can cause even more damage when use rectally. This is because the rectum is even more fragile than the vagina. So N9 should never be used during anal sex. Even a very small amount of nonoxynol-9 on a condom can cause damage to the rectum. This damage increases your chances of getting HIV from an infected partner.

Additional FDA Warning About Nonoxynol-9:

The FDA also requires that the labels of all spermicides that contain N9 warn that:

  • Nonoxynol-9 is for vaginal use only (not for rectal/anal use).
  • Use of N9 may increase the risk of getting HIV from an infected partner.
  • You should not use nonoxynol-9 if you or your sexual partner has HIV/AIDS.
  • You may experience vaginal irritation (burning, itching, or a rash) when using products that contain nonoxynol-9.

A Call to Action:

In 2000, the CDC wrote a letter that explained that results of a four year trial showed that women who used a nonoxynol-9 gel had become infected with HIV at about a 50% higher rate than women who used a placebo gel.Women had a higher risk of becoming infected the more often they used the N9 gel. Based on this study, the WHO and CDC began their own investigation of nonoxynol-9.

In May 2002, the CDC published new guidelines that cautioned people not to use N9 for disease prevention. In response to the CDC and WHO's concerns, women's health and HIV advocates, health groups, and scientists, along with the Global Campaign for Microbicide put out a call to action. The campaign asked condom companies and lubricant manufacturers to voluntarily remove nonoxynol-9 from their products.

In 2002, Kimono condoms were the first condom brand to discontinue adding nonoxynol-9 to its condoms. Johnson & Johnson (which makes K-Y lubricant) also stopped including N9 in its products. Then in 2004, Durex condoms became the first (and only) of the top three largest condom companies to stop making condoms and lubricants that contained nonoxynol-9. Since that time, Sir Richards Condoms and L. Condoms came on the market -- neither of these condom manufacturers include nonoxynol-9 in any of their products.


Centers for Disease Control and Prevention. U.S. Medical Eligibility Criteria for Contraceptive Use, 2010. MMWR Early Release 2010;59 May 28:1-86.

Department of Health and Human Services, Food and Drug Administration. (2007). Over-the-counter Vaginal Contraceptive and Spermicide Drug Products Containing Nonoxynol9; Required Labeling.[Docket No. 1980N-02801]:1-61a.

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