Prep (Preexposure Prophylaxis for HIV)
Medically reviewed by Drugs.com. Last updated on Apr 6, 2025.
What do I need to know about preexposure prophylaxis (PrEP) for HIV?
PrEP is medicine given to adults and adolescents to prevent HIV infection. PrEP may be given if tests show you are HIV-negative but your risk for infection is high. PrEP may be given as a pill or an injection. PrEP lowers the risk for infection but is not 100% effective. You will still need to use other methods to prevent exposure to HIV.
How may PrEP be given?
- Pills may be taken daily. Pills may instead by taken only when you plan to have sex. This is called on demand. For the on-demand schedule, you must take 2 pills 2 to 24 hours before you have sex. Then you take 1 pill 24 hours after sex and 1 pill 48 hours after sex. It is important to follow the schedule. Your healthcare provider can help you decide if the on-demand schedule is better for you than the daily schedule.
- An injection is given every 2 months.
What can I do to prevent or manage an HIV exposure?
- Get screened for HIV and sexually transmitted infections (STIs). HIV screening is recommended at least 1 time for everyone aged 13 to 64. Your provider will tell you if need regular screening, based on your risk for HIV infection. If you are sexually active, get tested for STIs at least 1 time each year. If you get an STI, have it treated right away.
- Have safe sex. Safe sex means having sex with a person who is HIV-negative or whose infection is controlled with medicines. It also means using condoms each time you have sex. Exposure happens when you have contact with another person's blood, semen, rectal fluid, or vaginal fluid. You are exposed if these fluids touch an open area of your skin, such as a cut, or touch a mucus membrane.
- Do not share needles or other injectable drug equipment. Use a needle exchange program to get clean needles. Do not share needles, syringes, rinse water, or anything else used to prepare drugs for injection. Ask about needle and equipment practices at any company you go to for a tattoo or body piercing. Only go to companies that are licensed. The company needs to use new needles and sterilized equipment for each client.
- Follow workplace safety rules if you are at risk of exposure. If you think you have been exposed, get first aid right away. If open skin was exposed, wash the area right away with soap and water. Use a gel hand cleaner if you do not have soap or running water. If your eyes were exposed, rinse them with water or saline (a salt solution). Move your eyelids with your fingers as you rinse. Keep contact lenses in while you rinse. Then remove and clean the lenses with contact lens cleaner. Follow workplace guidelines about reporting the possible exposure.
- Ask about pregnancy or breastfeeding. Tell your healthcare provider if you are planning to become pregnant and you are at risk for HIV infection. PrEP may help protect you and your baby from infection before and during pregnancy. PrEP may also be used while you are breastfeeding.
Treatment options
The following list of medications are related to or used in the treatment of this condition.
When should I seek immediate care?
- You have a fever.
- You have a rash.
- You have new muscle pain or pain in your back or abdomen.
- You urinate more often than usual, have blood in your urine, or have pain while urinating.
- You are more thirsty than usual.
- You have trouble swallowing or breathing.
When should I call my doctor?
- You have nausea or diarrhea.
- You are more tired than usual.
- You have new headaches, or you feel dizzy.
- You have trouble sleeping.
- Your eyes or skin turn yellow.
- You are not eating because of appetite loss.
- You are or may be pregnant.
- You have questions or concerns about your condition or care.
Care Agreement
You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your healthcare providers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.© Copyright Merative 2025 Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes.
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.