This guideline is for use primarily by healthcare professionals in the emergency
department, primary care and GP Out of Hours, for the assessment of individuals aged over 16 presenting following a potential sexual/non-occupational exposure to HIV.

Table of abbreviations

3.1 Overview of PEPSE

• PEPSE reduces the risk of transmission of HIV by almost 80%.
• It is generally given where transmission risk approaches/exceeds 0.1%.
• PEPSE is most effective if given within 24h of exposure but can be
  administered up to 72h. Beyond 72h, PEPSE is not effective.
• PEPSE is available at BSH, Emergency departments at BGH.

3.2 Risk of HIV transmission

Risk of transmission varies with:

• Nature of sexual contact
• HIV serostatus of source (and viral load)
  
  • If serostatus unknown, background prevalence of HIV in source risk
    group (e.g. MSM/Heterosexual, ethnicity, PWID etc.)
• Number of exposures within a 72h period (risk is cumulative)

Use tables 1 & 2 below, together with the flowchart above, to determine if PEPSE is
indicated.

3.3 Table 1: Source is known HIV+

If source is known HIV+ get details (NB: often the patient is in contact with the source, and can find out these details during the consultation):

• Consultant
• Treatment centre
• Treatment history (including details of drug resistance)
• HIV viral load (90% of patients on treatment have an undetectable viral load)

Undetectable = Untransmissible: Patients with viral load <40 CANNOT transmit HIV.

3.4 Table 2: Source HIV status unknown

• The percentages in this table are to help you calculate cumulative risk from
  multiple sexual exposures.
• High-risk exposures (in red) should be given PEPSE based on ONE sexual
  encounter, regardless of % risk.
• If source is on PrEP, DO NOT GIVE PEPSE.

NB: In Scotland in 2017 the only new HIV diagnoses in PWID were in GGC & Lanarkshire.

3.5 Special situations where it is appropriate to prescribe PEPSE despite calculated risk

• MSM who have had receptive anal intercourse (See Table 2)
• Multiple sexual encounters (within previous 72h) where cumulative risk likely exceeds 0.1% (Use Table 2 to calculate this risk)
• Sexual assault, involving female patient, receptive anal sex or traumatic vaginal sex, where the source is from a country of high HIV prevalence* (traumatic intercourse may increase transmission rates).
• Extreme anxiety from the patient (prescribe PEPSE and refer to sexual health clinic for further discussion).

* See “Blood Borne Viruses – Background Information for Risk Assessment”

• Provide 7-day PEPSE pack if indicated:
  
  • Emtricitabine/Tenofovir 200/245mg one tablet daily
  • Raltegravir 400mg twice daily.
• This is a starter pack: full treatment course is 28 days.
• Patient should be advised to seek review at BSH within 3 days.
• Pregnant women: There is limited experience of using PEPSE in this patient group, but nominally PEPSE appears to be well-tolerated and safe.

4.1 Extending PEPSE

If high-risk sex occurs during the last 2 days of the PEPSE course, extend the course for 48h after the exposure.

4.2 Missed doses

4.3 Adverse effects and interactions

Common adverse effects (may affect >10% patients)

• Nausea, vomiting, diarrhoea
• Headache
• Dizziness
• Rash
• Feeling weak

Drug-specific concerns:

• Emtricitabine/tenofovir
  
  • Renal Impairment: If baseline CrCl <80 mL/min, consider if the benefits of
    PEPSE outweigh the risks
• Raltegravir
  
  • Avoid Cytochrome P450 enzyme inducing medication (e.g. Rifampicin)
  • Do not take multivitamins/antacids containing Calcium, iron, magnesium or aluminium at the same time as Raltegravir (limits absorption; leave 4h either side)

This is done at Borders Sexual Health Clinic. Preferably the patient will be told to
telephone BSH to make an appointment within 3 days of being prescribed PEPSE.

• Web: www.borderssexualhealth.org.uk
• Email (Health professionals only): sexual.health2@borders.scot.nhs.uk
• Telephone: 01896 663700

All cases of suspected exposure to HBV should receive the first dose of a course of
vaccination unless the patient is known to be Hepatitis B immune.

• All cases should receive the first vaccination or booster of Hepatitis B vaccine.
• Baseline Bloods:
  
  • Patient immunised - HBsAb – check titre
  • Patient not immunised - HBcAb – check if already infected
• Vaccination can be beneficial up to 6 weeks after exposure.
• Hepatitis B immunoglobulin is indicated if the source is known to be an infectious hepatitis B carrier (defined as HBsAg positive).

There is no PEPSE available for Hepatitis C.

• Drug interactions: www.hiv-druginteractions.org
• 2015 BASHH guidelines:
  https://www.bashhguidelines.org/media/1027/pepse-2015.pdf
• Patient information leaflet:
  https://www.bhiva.org/file/ieJHUmCnjsWIM/PEP-HIVPA-leaflet_Oct_2014.docx