There are three regimens approved by the United States Food and Drug Administration (FDA) for use as HIV preexposure prophylaxis (PrEP): oral tenofovir DF-emtricitabine (TDF-FTC), oral tenofovir alafenamide-emtricitabine (TAF-FTC), and long-acting injectable cabotegravir (CAB-LA). During the baseline evaluation, all persons considered for starting HIV PrEP with any one of these medications should undergo assessment for the following:[1]
- Need for Nonoccupational HIV Postexposure Prophylaxis (PEP): Any significant exposures to HIV in the past 72 hours that would suggest a need to immediately start nonoccupational postexposure prophylaxis (PEP) should supersede the plan for starting HIV PrEP. Following completion of nonoccupational PEP, the individual can immediately transition to starting HIV PrEP if indicated. For details on the indications and management of nonoccupational PEP see the National HIV Curriculum lesson on Nonoccupational Postexposure Prophylaxis.
- Baseline Laboratory Studies: Prior to starting HIV PrEP, baseline laboratory studies, as outlined in detail in the next section, should be ordered to rule out preexisting HIV infection, to obtain baseline safety laboratory studies, and to evaluate for other important infectious diseases that are transmitted through sexual activity or injection drug use.
- Possible Acute HIV Infection: Any clinical manifestations that suggest acute (primary) HIV infection should prompt a thorough laboratory evaluation for acute HIV infection and should delay the start of HIV PrEP while awaiting the laboratory results. For details on the diagnosis and treatment of acute HIV, see the National HIV Curriculum lesson on Acute and Recent HIV Infection. The figure below summarizes the most common signs and symptoms associated with acute HIV (Figure 1).[1,2]