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Doctor and Patient

Post Exposure Prophylaxis

HIV Post Exposure Prophylaxis (PEP)


= After


= a situation where HIV has a chance to get into a persons bloodstream


= a treatment to stop an infection happening

Post Exposure Prophylaxis (PEP) is a course of anti-HIV medication that needs to be taken daily over a period of four weeks, the medication is given because it may prevent HIV infection after the virus has entered the body. The drugs have been available for HIV prevention since the early-to mid 1990s for health workers who have had 'needle-stick' or similar injuries. More recently, PEP has been made available under strict prescribing guidelines, to people who might have been exposed to HIV during sex, or who could have been in contact with an infected secretion, such as blood or saliva.

The sooner PEP is started, the more effective it is, ideally within one hour of exposure. Therefore, its important to act quickly when seeking PEP, preferably immediately, but no more than 72 hours after you were potentially exposed to HIV. By instituting PEP the risk of developing HIV can be reduced by 85 to 95%. It is important to follow the guidelines for PEP and meet the criteria, which will be discussed at consultation with a Doctor experienced in the treatment of HIV

The risk of acquiring HIV through vaginal sex is 1 in 1000 to 1 in 10,000, the risk through anal sex is 1 in 100 to 3 in 100 and through oral sex the risk is 3 in 10,000

After HIV (Human immunodeficiency Virus) gets in the bloodstream it takes a period of time, which can be hours to a few days, before it permanently infects the person. If action is taken within this short time period there is a chance of stopping HIV before the infection takes hold.

Questions the Doctor will ask

When assessing the risk factors the Doctor will require some information.

Type of Exposure:

3 Types of exposure in health care settings associated with significant risk

  • Precutaneous injury (needle stick, instruments, bone fragments which break the skin)

  • Exposure of broken skin abrasions, cuts, eczema, etc.

  • Exposure of mucous membranes including the eye

Exposure outside occupational settings, which may include sexual exposure to HIV, or sharing drug injecting equipment with someone with HIV, or significant exposure to contact with material which may be infected with HIV

Sexual exposure can also place the person at risk of other sexually transmitted infections, and of pregnancy. Sharing equipment for injecting drugs can expose the person to other blood borne viruses, for example Hepatitis B and Hepatitis C. Testing and follow up as appropriate should be done. Where an unintended pregnancy is a possible outcome emergency contraception will be offered.

Other details may include:

  • The person the unsafe sex was with

  • the sex involved, for example when it happened, was it oral, anal or vaginal sex

  • was a condom used, or did a condom split

  • rape (whether or not HIV status of source is known)

  • sharing of injecting equipment

  • needle-stick injury

  • blood transfusion

The patient will be counselled prior to having a HIV test, before PEP and after PEP.

Recommended Drugs for PEP

  • Truvada

  • Kaletra

Although the Doctor may use other combinations where appropriate

The Principles of Starting PEP Treatment

  • Start as soon as possible after significant exposure

  • Discuss the known short-term and unknown long-term adverse effects

  • Advise how to access help outside clinic opening hours

Side Effects

All of the anti retroviral agents have been associated with some side effects, many can be managed easily according to each symptom, some of the side effects include:

  • Nausea

  • Vomiting

  • Malaise

  • Fatigue

  • Headache

The Doctor will discuss any side effects or reactions and what to do, or if symptoms are causing distress, or if the symptoms cannot be managed the doctor will review another suitable drug.

PEP is not a cure for HIV and is not guaranteed to prevent HIV from taking hold once the virus has entered the body. Condoms and lube for sex remain the most efficient way of staying safe from HIV

PEP makes infection with HIV a lot less likely, but PEP doesn't work every time, some who have taken it still end up with HIV infection afterwards. This failure may be due to some anti-HIV drugs don't work against some strains of HIV. Also it is more likely to fail if the medication is not taken properly, or not taken soon enough.

PEP: The Basic Facts

  • could stop someone getting HIV

  • involves taking anti-HIV drugs for 4 weeks

  • must be started as soon as possible after unsafe sex or a condom not working - and definitely within 72 hours (3 days)

  • has side effects

  • is not guaranteed to work

Where to get PEP

  • The Sunshine Clinic

  • Sexual Health Clinics within opening hours

  • Hospitals (usually A/E departments)

If already HIV positive, and the PEP is for someone you had sex with, contact your HIV clinic.

Not all of these places in every part of the country will have PEP or have procedures in place to offer PEP.

The Doctor will make a decision based on strict prescribing criteria and after making a judgment on the likely risks.

Before receiving PEP, you will probably be asked to take an HIV test. It is essential to check that you did not already have HIV before this risk. This is because taking PEP, if already HIV positive (have the virus), can cause drug resistance, and cause

complications for treating HIV in the future.

Staying Safe After PEP

PEP is not a replacement for condoms. Condoms, when used properly are still the easiest and most effective way of reducing the risk of HIV being picked up or passed on.

Hepatitis B Prophylaxis

At the Sunshine Clinic Hepatitis B prophylaxis is available. It includes an accelerated course of Hepatitis B vaccination. Risk assessment is done at the time of consultation. In high-risk exposure Hepatitis B Immunoglobulins are indicated.

Hepatitis B is many times more infectious than Hepatitis C and HIV. The risk of acquiring HIV, Hepatitis C and Hepatitis B with needle stick injury is 0.3, 3 and 30 percent respectively.

Unfortunately there is no prophylaxis available for Hepatitis C infection. Blood is tested 3 months and 6 months after significant exposure for Hepatitis B and C infection.

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