The pharmacological management of Human immunodeficiency virus (HIV) infection and acquired immune deficiency syndrome includes the therapy with several antiretroviral drug classes which interfere with different steps in the HIV life-cycle. The concomitant use of multiple drugs with different mechanisms of action is called Highly Active Anti Retroviral Therapy and improves the life of an infected patient, reducing the incidence of the opportunistic infections and maintaining the functions of the immune system at an acceptable level. The first antiretroviral therapeutic drug was a nucleoside-like reverse transcriptase inhibitor – zidovudine/azidothymidine. The best choice in the HIV infection therapy is to suppress the replication as much as possible, reducing the potential mutations which lead to the superior copies. Protein Inhibitors are inhibiting the viral replication by blocking the HIV proteases, enzymes that are important for the proteolysis of protein precursors that are necessary for the production of infectious mature viral particles.