How to avoid HIV
The main way to prevent HIV infection is to reduce the risk of exposure by using a condom when you have sex and not sharing needles and other equipment used for injecting drugs.
HIV treatment with antiretrovirals substantially reduces the risk of passing the virus onto someone else.
Knowing your HIV status and that of your partner is important and if you are at regular risk of potential exposure to HIV you should have a regular HIV test.
HIV can be transmitted by having vaginal or anal sex without a condom. There is also a risk of transmission through oral sex, but this risk is much lower.
HIV can also be caught from sharing sex toys with someone infected with HIV.
The best way to prevent HIV and other sexually transmitted infections (STIs) is to use a condom for penetrative sex and a dental dam or condom for oral sex.
Condoms come in a variety of shapes, colours, textures, materials and flavours. Both male and female condoms are available. A condom is the most effective form of protection against HIV and other STIs. It can be used for vaginal and anal sex, and for oral sex performed on men.
HIV can be passed on before ejaculation, through "pre-cum" and vaginal secretions, and from the anus.
It is very important that condoms are put on before any sexual contact occurs between the penis, vagina, mouth or anus.
Lubricant, or lube, is often used to enhance sexual pleasure and safety, by adding moisture to either the vagina or anus during sex. Lubricant can make sex safer by reducing the risk of vaginal or anal tears caused by dryness or friction, and it can also prevent a condom from tearing.
Only water-based lubricant (such as KY Jelly), rather than an oil-based lubricant (such as Vaseline, massage oil and baby oil) should be used with condoms. Oil-based lubricants weaken the latex in condoms and can cause them to break or tear.
Pre-exposure prophylaxis (PrEP)
PrEP is a new way of using anti-retroviral drugs (ARVs) - usually used for treating people with newly diagnosed HIV - to stop those at the very highest risk from contracting the virus.
Recent evidence shows PrEP can be highly effective in preventing HIV infection as long as the drugs are taken regularly when people are at risk.
Evidence of effectiveness is strongest for men who have sex without a condom with multiple male partners.
For further information on PrEP, including its effectiveness and availability and potential side-effects, please see our FAQs.
A dental dam is a small sheet of latex that works as a barrier between the mouth and the vagina or anus to reduce the risk of STIs during oral sex.
Sharing needles and injecting equipment
If you inject drugs, don't share needles or syringes, or other injecting equipment such as spoons and swabs, as this could expose you to HIV and other viruses found in the blood, such as hepatitis C.
Many local authorities and pharmacies offer needle exchange programmes, where used needles can be exchanged for clean ones. If you are a heroin user, consider enrolling in a methadone programme. Methadone can be taken as a liquid, so it reduces your risk of getting HIV.
A GP or drug counsellor should be able to advise you about both needle exchange programmes and methadone programmes.
If you're having a tattoo or piercing, it's important that a clean, sterilised needle is used.
See the FPA website for a range of downloadable leaflets on contraception and sexually transmitted infections.