Pre-exposure prophylaxis (PrEP) is an effective HIV prevention strategy that consists in the use of antiretroviral drugs by seronegative people at risk of HIV. Negative perceptions, inadequate understanding, and access barriers have been associated with decreased medication adherence. Manaus is the largest city in the Brazilian Amazon, where the incidence of HIV/AIDS is high, and the rates of adherence to the antiretroviral treatment for HIV and PrEP are low. In this qualitative study among PrEP users, mostly MSM, we explored perceptions, knowledge, and access barriers. We conducted 21 in-depth interviews with an intentionally sampled group of participants who had used PrEP at least once in their lifetime, selected through the snowball technique, between April and July 2022. A thematic analysis was conducted with a predominantly inductive approach. We highlight three relevant themes: (i) access to information about PrEP and its influences on users, (ii) access, monitoring, and barriers encountered, and (iii) facilitators for PrEP adherence and sexual behaviors. One of the negative perceptions identified in the study involves a misunderstanding of the association between PrEP users and the HIV/AIDS status. Participants revealed that some non-PrEP users suspect that individuals claiming PrEP usage are concealing an HIV-positive status to engage in unprotected sex. Lack of information by health professionals regarding HIV prevention methods poses significant barriers to PrEP access and adherence. Participants emphasized social media’s crucial role in PrEP awareness. The results suggest a need to increase digital outreach regarding PrEP, decentralize PrEP services, and provide comprehensive healthcare training to improve the effectiveness of the preventive measure.