Prevention

There are several ways to avoid or reduce your risk of STDs or STIs.

• Abstain. The most effective way to avoid STIs is to not have (abstain from) sex.
• Stay with one uninfected partner. Another reliable way of avoiding STIs is to stay in a long-term relationship in which both people have sex only with each other and neither partner is infected.
• Wait and test. Avoid vaginal and anal intercourse with new partners until you have both been tested for STIs. Oral sex is less risky, but use a latex condom or dental dam to prevent skin-to-skin contact between the oral and genital mucous membranes.

• Get vaccinated. Getting vaccinated early, before sexual exposure, is also effective in preventing certain types of STIs. Vaccines are available to prevent human papillomavirus (HPV), hepatitis A and hepatitis B.

  The Centers for Disease Control and Prevention (CDC) recommends the HPV vaccine for girls and boys ages 11 and 12, although it can be given as early as age 9. If not fully vaccinated at ages 11 and 12, the CDC recommends getting the vaccine through age 26.

  The hepatitis B vaccine is usually given to newborns, and the hepatitis A vaccine is recommended for 1-year-olds. Both vaccines are recommended for people who aren't already immune to these diseases and for those who are at increased risk of infection, such as men who have sex with men and IV drug users.

• Use condoms and dental dams consistently and correctly. Use a new latex condom or dental dam for each sex act, whether oral, vaginal or anal. Never use an oil-based lubricant, such as petroleum jelly, with a latex condom or dental dam.

  Condoms made from natural membranes are not recommended because they're not effective at preventing STIs. Also, keep in mind that while latex condoms reduce your risk of exposure to most STIs, they provide less protection for STIs involving exposed genital sores, such as HPV or herpes.

  Also, nonbarrier forms of contraception, such as birth control pills or intrauterine devices (IUDs), don't protect against STIs.

• Don't drink alcohol excessively or use drugs. If you're under the influence, you're more likely to take sexual risks.
• Communicate. Before any serious sexual contact, communicate with your partner about practicing safer sex. Be sure you specifically agree on what activities will and won't be OK.
• Consider male circumcision. For men, there's evidence that circumcision can help reduce the risk of acquiring HIV from a woman with HIV by as much as 60%. Male circumcision may also help prevent transmission of genital HPV and genital herpes.

• Consider using preexposure prophylaxis (PrEP). The Food and Drug Administration (FDA) has approved the use of two combination drugs to reduce the risk of HIV infection in people who are at very high risk. They're emtricitabine plus tenofovir disoproxil fumarate (Truvada) and emtricitabine plus tenofovir alafenamide fumarate (Descovy).

  Your doctor will prescribe these drugs for HIV prevention only if you don't already have HIV. You will need an HIV test before you start taking PrEP and then every three months as long as you're taking it.

  Your doctor will also test your kidney function before prescribing Truvada and continue to test it every six months. If you have hepatitis B, you should be evaluated by an infectious disease or liver specialist before beginning therapy.

  These drugs must be taken every day, exactly as prescribed. If you use Truvada daily, you can lower your risk of getting HIV from sex by about 99% and from injection drug use by more than 74% percent, according to the U.S. Centers for Disease Control and Prevention. Research suggests that Descovy is similarly effective in reducing the risk of getting HIV from sex. However, Descovy hasn't been studied in people who have receptive vaginal sex. Using additional prevention, such as condoms, can lower your risk even more and prevent other STIs.