“…Concentrations of nonnucleoside reverse transcriptase inhibitors (NNRTIs) in seminal plasma are consistently measurable, although lower than those in blood plasma (14,21). Penetration of PIs in semen is poor, and seminal concentrations of PIs seem to be dependent on the degree of protein binding, with the weakest-bound drugs (amprenavir and indinavir) having the highest concentrations (5,13,19,20,23). In contrast to those observed for PIs, NRTI seminal plasma concentrations are similar to or higher than concentrations in blood plasma (5,6,13,21).…”