Pre Exposure Prophylaxis or PrEP is a highly effective tool in preventing HIV if taken consistently and correctly. As long as someone is adherent to daily dosing of PrEP, Post Exposure Prophylaxis (PEP) would not be recommended after an exposure to HIV as they are already protected.
So generally speaking no – PEP would not be recommended if the individual is on PrEP.
However if the individual has poor adherence and has been missing doses of PrEP, and then had an exposure to HIV, PEP could be considered. Assessments for PEP are done through urgent care or emergency within 72 hours of potential exposure.
Hope this is helpful.