Antiretrovirals

Antiretrovirals

Antiretrovirals are a class of medications used to treat infections caused by retroviruses, primarily HIV (Human Immunodeficiency Virus). These drugs work by inhibiting the replication of the virus within the host's body, thereby reducing the viral load and improving the immune function of the patient. Antiretrovirals are a cornerstone in the management of HIV/AIDS and have significantly improved the prognosis and quality of life for individuals living with the virus.

Mechanism of Action

Antiretrovirals target different stages of the HIV life cycle. The main classes of antiretroviral drugs include:

• Nucleoside Reverse Transcriptase Inhibitors (NRTIs): These drugs mimic the natural nucleosides used by the virus to synthesize DNA, thereby terminating the DNA chain and preventing viral replication.

• Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs): NNRTIs bind to and inhibit the reverse transcriptase enzyme, preventing the conversion of viral RNA into DNA.

• Protease Inhibitors (PIs): These inhibit the protease enzyme, which is essential for the maturation of infectious viral particles.

• Integrase Inhibitors: These drugs block the integrase enzyme, preventing the integration of viral DNA into the host genome.

• Entry Inhibitors: These prevent the virus from entering the host cells by blocking the fusion of the viral envelope with the host cell membrane.

• Pharmacokinetic Enhancers: These are used to boost the effectiveness of other antiretrovirals by inhibiting enzymes that metabolize them, thereby increasing their concentration in the blood.

Treatment Regimens

The standard treatment for HIV infection is known as Highly Active Antiretroviral Therapy (HAART), which typically involves a combination of three or more antiretroviral drugs from at least two different classes. This approach helps to prevent the development of drug resistance and maximizes viral suppression.

Side Effects

While antiretrovirals are generally well-tolerated, they can cause side effects, which may include nausea, diarrhea, fatigue, and metabolic changes. Long-term use can also lead to more serious complications such as liver toxicity, kidney damage, and cardiovascular issues.

Resistance

HIV can develop resistance to antiretroviral drugs, which is why adherence to prescribed regimens is crucial. Resistance testing is often performed to guide the selection of effective drug combinations.

Global Impact

Antiretrovirals have transformed HIV from a fatal disease to a manageable chronic condition. Access to these medications has been a major focus of global health initiatives, particularly in low- and middle-income countries where the burden of HIV is highest.

Also see

• HIV/AIDS
• Viral Load
• CD4 Count
• Opportunistic Infections
• Pre-exposure Prophylaxis (PrEP)
• Post-exposure Prophylaxis (PEP)