Zidovudine

• Zidovudine is an antiretroviral drug classified as a nucleoside reverse transcriptase inhibitor (NRTI).
• It works by inhibiting the reverse transcriptase enzyme, which is essential for HIV replication.
• The medication is primarily used to treat HIV-1 infection and prevent mother-to-child transmission.
• Dosage is individualized and typically part of a combination therapy regimen.
• Common side effects include nausea, headache, and fatigue, while more serious effects can occur.

What is Zidovudine: Mechanism of Action

Zidovudine is an antiretroviral medication, specifically a nucleoside reverse transcriptase inhibitor (NRTI), used in the treatment of human immunodeficiency virus (HIV) infection. It was one of the first drugs approved for HIV treatment and remains a foundational component in many therapeutic regimens.

This medication works by targeting the reverse transcriptase enzyme, which is vital for the HIV life cycle. HIV, a retrovirus, uses reverse transcriptase to convert its RNA genome into DNA, a necessary step before it can integrate into the host cell’s DNA. Zidovudine, once phosphorylated into its active triphosphate form, mimics natural nucleosides and is incorporated into the nascent viral DNA chain by reverse transcriptase. This incorporation causes premature chain termination, effectively halting the synthesis of new viral DNA and preventing the virus from replicating. This mechanism of action is crucial in reducing the viral load in infected individuals.

Zidovudine Dosage and Uses

Zidovudine is primarily used for the treatment of HIV-1 infection in adults and children, often as part of a highly active antiretroviral therapy (HAART) regimen. Its efficacy is significantly enhanced when combined with other antiretroviral drugs, which helps to prevent the development of drug resistance and achieve better viral suppression.

Key uses for Zidovudine include:

• Treatment of established HIV-1 infection.
• Prevention of mother-to-child transmission of HIV during pregnancy, labor, and delivery, and in newborns.
• Post-exposure prophylaxis (PEP) in individuals who may have been exposed to HIV, in combination with other antiretrovirals.

The specific zidovudine dosage and uses are highly individualized, determined by a healthcare professional based on the patient’s age, weight, kidney function, and the severity of their HIV infection. It is crucial to adhere strictly to the prescribed regimen to maximize effectiveness and minimize the risk of resistance.

Zidovudine Side Effects

Like all medications, Zidovudine can cause side effects, which range from mild to severe. Patients should discuss any concerns with their healthcare provider.

Common zidovudine side effects often include:

• Nausea and vomiting
• Headache
• Fatigue and weakness
• Insomnia
• Anemia (low red blood cell count)
• Neutropenia (low white blood cell count)

More serious, though less common, side effects can include severe anemia, myopathy (muscle weakness or pain), lactic acidosis (a buildup of lactic acid in the blood), and severe hepatomegaly with steatosis (enlarged liver with fat accumulation). Regular monitoring of blood counts and liver function is essential during treatment to detect and manage these potential adverse effects promptly. According to the Centers for Disease Control and Prevention (CDC), adherence to antiretroviral therapy, including managing side effects, is critical for successful long-term outcomes in HIV management.