Using condoms during anal and vaginal sex will stop most types of STI. Use latex condoms and water-soluble lube, and squeeze out air from the tip of the condom. There are also non-latex alternatives available, but if you use lambskin, cover it with a latex condom. Pulling out before you come might guard against infection if the condom breaks during intercourse.
If the condom breaks, urinating immediately after sex and washing your penis with soap and water may help prevent urethral infections, although this method is not very reliable.
During oral sex, don’t get semen, blood or vaginal fluid in your mouth, since there is a risk (low) of picking up HIV and hepatitis B this way. Using a condom prevents spreading HIV and other STIs from oral sex.
It is also advisable not to perform oral sex within two hours of flossing or brushing your teeth, since these activities could cause cuts in the gums, providing entry points for HIV.
Similarly, you should be careful after recent dental surgery, or if you have problems with bleeding gums or other sores in your mouth. If you’re worried because someone has performed oral sex on you, washing and urinating may help, as noted above. Performing oral sex may also expose you to hepatitis A and parasites. The virus can be present anywhere in the anal area or on fingers which have touched the anus of an infected person.
Rimming is risky for the person doing the rimming, since it may expose them to parasites and hepatitis A. You and your partners should wash the anal area thoroughly, before engaging in any oral contact near the anus. Douching is not a good idea, since it can damage the anal canal and drive infections further in.
Sex toys can pass on parasites, hepatitis A, HIV and a number of other STIs. Cover sex toys with condoms, or wash them carefully with bleach and rinse well before and after using. Keep in mind that the lining of the anus is easily damaged by fists, dildos and other sex toys, so precautions should be taken.
Routine testing is very important for people who have casual sex. You can pick up a number of STIs without having symptoms, so testing may be your only way of knowing whether or not you’re infected.
If you have casual sex, get a syphilis blood test at least once a year, depending on how many different partners you have had, and whether or not you had unprotected sex. You may also need urethral, anal and throat swabs for gonorrhea and chlamydia, depending on what sexual activities you engage in.
Get an HIV blood test, to find out if you’ve been infected with HIV. Don’t assume you’re negative because you feel well, or because you haven’t had unsafe sex for a long time. Also, don’t assume that your sexual partners are HIV negative. Keep in mind that there is now a lot you can do to stay well, if you test positive. Don’t wait until it’s too late.
Consider getting vaccinated for hepatitis A and hepatitis B, if you are at risk (i.e. multiple sexual partners, or sharing needles). Inform your sexual partner(s) if you have an STI. Speak to a nurse or counsellor first to decide whom you need to inform. Do not donate blood, semen or organs, unless you know you have never been infected with HIV, hepatitis or syphilis.