HIV (human immunodeficiency virus) is a virus that can be transmitted by bodily fluids such as blood, semen and vaginal fluids. This virus infects and kills immune cells, which causes a gradual depletion of the immune system called AIDS (acquired immunodeficiency syndrome). There are a variety of medications that can be taken to slow this virus's progression.
Goals
HIV drugs are unable to cure an HIV infection. Instead, treatment for HIV has several goals, Project Inform explains. One goal of HIV medications is to reduce the number of copies of the HIV virus in the patient's bloodstream. Anti-HIV treatment also aims to keep the patient's immune system healthy for as long as possible in order to optimize the patient's ability to fight infections. Treatment plans are also designed to minimize the side effects that the patient experiences.
HIV Life Cycle and Drugs
HIV has a complex life cycle and different HIV drugs block different aspects of the virus's reproduction. HIV initially infects cells by binding specifically to a protein called CD4, which can be found on certain kinds of white blood cells. The virus uses many proteins that are initially fused together. Thus, once it is inside the cell, it needs to break up these proteins (using an enzyme called a protease) in order to be able to replicate. The virus then makes copies of its genetic material and transfers them into the cell's DNA. This causes the cell to make copies of HIV, which then escapes once the cell's resources have been exhausted.
Drug Mechanisms
Anti-HIV drugs work to block HIV's life cycle at many different stages, the FDA explains. One class of medications, called fusion inhibitors, work to keep the virus from entering into the immune cells. Protease inhibitors prevent the virus from unpackaging its proteins. Reverse transcriptase inhibitors prevent the virus from making copies of its own genetic material. Integrase inhibitors, on the other hand, keep the virus from inserting its DNA into the host cells. Most patients take a combination of these medications in order to combat the infection at several different stages.
Starting Treatment
Patients who are HIV-positive do not need to begin taking anti-HIV medications immediately, AIDSInfo explains. HIV medications require the patients to adhere to a strict regimen and can have some unpleasant side effects, including nausea, muscle pain, diarrhea, rashes and liver damage. When a patient needs to begin treatment depends on his viral load, overall health and the strength of his immune system. AIDSInfo explains that patients need to begin treatment if they start developing opportunistic infections, develop a low CD4 cell count (the cells that HIV infects), become pregnant, develop kidney disease or if they are being treated for hepatitis B.
Treatment Regimens
Because there are so many different kinds of drugs that can be used to treat HIV infections, a customized regimen can usually be developed by the patient's physician. Things that can affect which drugs the patient takes include the number of pills/dosing schedule that the patient will need to follow, interactions with other medications that the patient is taking (including other anti-HIV medications), other medical conditions that the patient has, as well as how the patient's particular strain of HIV responds to treatment.
