Lamivudine – Uses, Dosage, Side Effects & More

When working with lamivudine, a nucleoside reverse transcriptase inhibitor (NRTI) used to treat HIV infection and chronic hepatitis B. Also known as Epivir or Zeffix, it blocks the viral enzyme reverse transcriptase, preventing the virus from copying its genetic material. This action makes lamivudine a core component of many antiretroviral therapy (ART) regimens and hepatitis B treatment protocols.

Key Related Entities

The effectiveness of lamivudine can’t be understood in isolation. It is tightly linked to HIV, the virus that attacks the immune system, and human immunodeficiency virus, which requires lifelong suppression. Lamivudine also interacts with hepatitis B, a liver‑affecting virus that benefits from the drug’s ability to lower viral load and reduce liver inflammation. As an NRTI, lamivudine belongs to a class of drugs that mimic natural nucleosides, get incorporated into viral DNA, and cause chain termination. Finally, the broader framework of antiretroviral therapy, which combines several agents to achieve durable viral suppression, relies on lamivudine’s potency and relatively low toxicity.

Understanding these connections helps answer common questions. Lamivudine’s typical adult dosage is 150 mg once daily for hepatitis B and 300 mg daily (often split into 150 mg twice) when part of an HIV regimen. The drug comes in tablets, oral solution, and pediatric formulations, making it adaptable for different age groups. Common side effects include headache, nausea, and fatigue, but serious adverse events such as lactic acidosis are rare. Resistance can develop, especially when lamivudine is used as a single agent; mutations in the reverse transcriptase gene (e.g., M184V) reduce its effectiveness, which is why clinicians pair it with other antiretrovirals. Monitoring viral load and liver enzymes regularly lets patients and providers catch resistance early and adjust therapy.

Beyond dosage and safety, patients often wonder how lamivudine fits into their daily lives. The drug’s low pill burden means it’s easy to combine with other agents in a single tablet—think of fixed‑dose combos like Truvada (emtricitabine/tenofovir) where lamivudine can be swapped for emtricitabine without losing efficacy. For pregnant women living with HIV, lamivudine is classified as safe and can help prevent mother‑to‑child transmission when used throughout pregnancy. In hepatitis B, continued therapy can lead to seroconversion and long‑term liver health, especially when started early. If you’re starting lamivudine, talk to your provider about renal function, as dose adjustments may be needed for reduced kidney clearance. Ready to dive deeper? Below you’ll find a curated collection of articles covering everything from sleep disturbances on steroids to thyroid effects of fenofibrate, all selected to give you a broader view of how medications interact, how side effects manifest, and what practical steps you can take. The next sections will give you detailed guidance, real‑world tips, and evidence‑based answers that complement the lamivudine overview you just read.