Post-exposure prophylaxis - HIV

Category: Infections and parasites

Topics: HIV, Sexually transmissible infections

Quick facts:

  • Post-exposure prophylaxis (PEP) is a 4-week course of medication to help prevent Human Immunodeficiency Virus (HIV) infection after possible exposure to infectious blood or bodily fluids.
  • PEP must be started as soon as possible after, and within 72 hours, of possible exposure to HIV.
  • PEP is available to anyone who may have been exposed to HIV, either at work (e.g. needlestick injury) or outside of work.
  • PEP requires a prescription.
  • PEP is available from most public hospitals in Queensland and specialist HIV support services, sexual health clinics, and some general practitioners.

PEP greatly decreases the chance of acquiring HIV after potential exposure, though is not a guarantee. To provide the maximum protection, the full course of PEP must be completed.

A course of PEP does not provide lasting protection for future HIV exposures. If you are exposed to HIV again, you should seek new PEP treatment.

For occupational exposures in a Queensland Health workplace

For potential occupational HIV exposures, follow the local blood and body fluid exposure management procedure and refer to the Queensland Health Occupational Exposure to Blood and Body Fluids Procedure for guidance on managing exposures and accessing PEP : Occupational Exposure to Blood and Body Fluids Procedure (PDF 369 KB).

Transmission

HIV may be transmitted by contact with the blood, semen or vaginal fluids of a person living with HIV through:

  • Unprotected sex – anal or vaginal.
  • Sharing needles or injecting equipment contaminated with blood.

HIV may also be transmitted through donated blood products. However, the risk of acquiring HIV from these products in Australia is extremely low. All donated blood, organs, tissues and semen in Australia are routinely screened for HIV.

HIV can also be transmitted from a person living with HIV to their child during pregnancy, childbirth or breastfeeding.

Effective treatment is available for people living with HIV. When treatment is taken as prescribed, the risk of transmission to others is extremely low. If this information is known, health professionals will consider this when assessing transmission risk.

Treatment

A person who may have been exposed to HIV through contact with blood or body fluids from an HIV-positive person should seek medical advice as soon as possible.

To determine whether PEP is needed, an assessment of HIV transmission risk will be done. A person will be asked about the exposure and other risks and have a blood test to check for HIV and other sexually transmissible infections (STIs).

A prescription for PEP can be obtained from most public hospitals in Queensland, specialist HIV support services or sexual health clinics and some general practitioners. People wishing to access PEP should telephone the service for opening hours and advise clinical staff that PEP may be required.

People presenting to hospital emergency departments, or where there is limited access to the full 4-week supply, may receive a smaller supply of medications to start with. Following this, a follow-up appointment with a specialist PEP provider is necessary to obtain the full 4-week course. It is important the full 4-week course is completed to provide the best protection from HIV infection.

PEP medications may cause side effects including abdominal pain, diarrhoea or headaches throughout the 4-week course.

It is important to take the PEP medication as prescribed, so it is most effective.

A follow-up appointment is necessary after finishing the course of PEP so further HIV testing can be done.

Prevention

Practising safe sex and safer injecting practices remain the best ways to prevent HIV transmission. This includes:

  • always using condoms with water-based lubricant
  • using sterile injecting equipment.

Your health professional may also discuss options for HIV Pre Exposure Prophylaxis (PrEP) medications. Pre-exposure prophylaxis - HIV - qld.gov.au

Preventing HIV transmission while taking PEP

Until the follow-up blood test shows that you do not have HIV, you should:

  • use safe sex practices, including condoms, to protect sexual partners
  • not donate blood or blood products, body tissue, breast milk or sperm
  • not share injecting equipment, tattooing or body piercing equipment
  • seek medical advice regarding pregnancy and/or breastfeeding.

Other resources

  • For information on PEP in Arabic, Chinese, Filipino, Japanese, Korean, Spanish, Thai, or Vietnamese, visit the StaySTIfree website. Other translated resources about STIs are available from the Ethnic Communities Council of Queensland.
  • For Australia wide information visit the Get PEP website.

Related content

Help and assistance

Get qualified health advice 24/7 for the cost of a local call. 13 HEALTH (13 43 25 84).

This factsheet provides general information and is not intended to replace the need to see a health professional or have a sexual health check. For more information on HIV PEP please talk to a healthcare provider. A doctor, nurse or health worker can assist with:

  • providing appropriate tests, treatment and information about how to prevent STIs
  • helping people to ensure that their sexual partners get tested and treated

In an emergency

If you are in an emergency situation, call 000

Health advice

Get qualified health advice 24/7 for the cost of a local call: 13 HEALTH (13 43 25 84)

Last updated:
9 September 2026