Prescribing PEP

Adverse effects caused by antiretrovirals and their impact on adherence are well recognised. Drug choice is determined by: safety, tolerability, ease of dosing, HIV resistance patterns in the local infected population, the medical history of the exposed person, and cost. When known, source information concerning antiretroviral treatment history and the results of past HIV resistance testing may also determine the choice of drugs for PEP.

We now have PEP regimens that are well tolerated, with minimal side effects, drug–drug interactions, dosing requirements and pill burden.

Clinicians must inform patients who are prescribed PEP about the following:

  • PEP provides high levels of protection but does not prevent 100% of infections
  • the importance of adherence
  • the potential adverse effects of treatment and possible drug interactions
  • measures for preventing re-exposure to HIV
  • follow-up HIV testing
  • HIV seroconversion signs and symptoms.

PEP should generally not be prescribed after 72 hours, but may be considered on a case-by-case basis in consultation with a specialist.

Linkage to a specialist for discussion regarding PrEP should be considered. See the PrEP guidelines for further guidance at

A 28-day course of PEP is recommended. Patients presenting to emergency departments should receive a 5–7 days starter pack and be provided with a referral for a follow-up appointment with a specialist PEP provider. Patients presenting to sexual health clinics, HIV clinics or s100 prescriber GPs may be given a prescription for the entire 28 days.19