The human immunodeficiency virus or HIV is the virus that can lead to acquired immunodeficiency syndrome or AIDS. The virus is transmitted primarily through sexual contact---vaginal, oral or anal---but it also may spread via shared syringe needles and blood transfusions. The Mayo Clinic reports that HIV, which hinders your immune system, allows your body to become vulnerable to infections and cancers that you might otherwise be able to resist. There is no cure for the viral infection, but there are many drugs used to treat it.
NRTIs
Nucleoside analogue reverse transcriptase inhibitors or NRTIs are one type of drug among many called anti-retrovirals. The Mayo Clinic states NRTIs were the originals of this type of medication. NRTIs work by preventing the HIV enzyme reverse transcriptase from replicating itself. These types of medicines include Ziagen (generic: abavavir), Zerit (generic: stavudine), Videx (generic: didanosine), Epivir (generic: lamivudine) and Retrovir (generic: zidovudine). There also is an AIDS medication called Emtriva (generic: emtricitabine) that may be prescribed combined with other drugs. Typical side effects include vomiting, nausea, fatigue, pain in the abdomen and diarrhea.
PIs
PIs or protease inhibitors work in much the same way as NRTIs, but PIs work on the HIV protease enzyme, and at a point later in the development of cell replication. PIs essentially disorganize HIV cells, which prevents them from being infectious. These kinds of drugs include---but are not limited to---Prezista (generic: darunavir), Aptivus (generic: tipranavir), Agenerase (generic: amprenavir) and Invirase (generic: saquinavir). Side effects are similar to those of NRTIs.
NNRTIs
Non-nucleoside reverse transcriptase inhibitors function differently in that they combine with the reverse transcriptase enzyme to nullify its effect. These drugs are called such names as Intelence (generic: etravirine), Sustiva (generic: efavirenz) and Rescriptor (generic: delavirdine). Side effects include skin rash and degeneration of mood disorders.
Fusion Inhibitors
Fusion inhibitors such as Fuzeon (generic: enfuvirtide) is used to fight the strains of HIV that are resistant to drugs. Fusion inhibitors function by stopping the HIV cell's membrane from joining with nearby cells' membranes that are healthy.
Integrase Inhibitors
Some people with the HIV infection can become resistant to typical treatments for the disease. For this reason, your physician may prescribe Isentress (generic: raltegravir) along with other AIDS drugs. The Mayo Clinic reports that this drug stops the DNA of HIV from joining your DNA by stopping the integrase enzyme of HIV from replicating. Side effects include headaches, fevers, nausea and diarrhea.
