Lamivudine: Uses, Dosage, and Key Facts

When you read about Lamivudine, a nucleoside analogue antiviral used to treat HIV and hepatitis B infections. Also known as 3TC, it belongs to the class of nucleoside reverse transcriptase inhibitors, agents that block the reverse transcriptase enzyme. The drug is a cornerstone of antiretroviral therapy, combination regimens designed to suppress viral replication and is prescribed for people living with HIV, the human immunodeficiency virus that attacks the immune system or chronic hepatitis B, a liver infection caused by the hepatitis B virus.

Lamivudine works by mimicking the natural building blocks of viral DNA, so when reverse transcriptase tries to copy the virus’s genetic material, the drug gets incorporated and stops the chain. This mechanism reduces the viral load, which in turn slows disease progression and improves immune health. Because it targets a specific step in the viral life‑cycle, Lamivudine is often paired with drugs that attack other stages, like protease inhibitors or integrase blockers. This multi‑drug approach not only boosts efficacy but also cuts down the chance of resistance. Studies show that patients on a Lamivudine‑based regimen can achieve undetectable viral loads within weeks, especially when adherence is high and dosing is consistent.

Practical Guidance for Patients and Providers

The typical adult dose for HIV is 300 mg once daily, taken with or without food. For hepatitis B, the recommended dose is also 300 mg daily, but some clinicians adjust based on kidney function because the drug is cleared renally. Common side effects include mild headache, fatigue, and occasional nausea—most people tolerate the medication well. Rarely, patients may experience liver enzyme elevations or lactic acidosis, so regular monitoring is advised, especially during the first few months. When prescribing Lamivudine, doctors check for interactions with other antiretrovirals, certain antibiotics, and some cholesterol‑lowering medicines. The drug doesn’t usually cause severe drug‑drug problems, but it can increase levels of drugs that are metabolized by the kidneys. Patients should inform their healthcare team about over‑the‑counter supplements, as a few herbal products can affect kidney clearance.

Our collection below dives deeper into these topics. You’ll find easy‑to‑follow dosage charts, side‑effect management tips, and side‑by‑side comparisons of Lamivudine with other NRTIs like tenofovir and abacavir. Whether you’re starting therapy, switching regimens, or just curious about how Lamivudine fits into the broader landscape of HIV and hepatitis B treatment, the articles ahead give you the practical details you need to make informed decisions.