Lamivudine is indicated for the treatment of chronic hepatitis B in patients who show evidence of viral replication and active liver inflammation.

Lamivudine is a synthetic nucleoside analogue. Inside the cells, lamivudine is converted into lamivudine triphosphate. The monophosphate form of lamivudine is incorporated into viral DNA by hepatitis B virus (HBV) polymerase, which leads to termination of the DNA chain. Lamivudine triphosphate also inhibits RNA- and DNA-dependent DNA polymerase activities of HIV-1 reverse transcriptase (RT). It is a very weak inhibitor of mammalian alpha, beta, and gamma DNA polymerases.

The recommended oral dose of Lamivudine for the treatment of chronic hepatitis B in adults is 100 mg once daily.

Trimethoprim 160 mg / Sulfamethoxazole 800 mg taken once daily has been shown to increase lamivudine exposure (AUC). The effects of higher doses of trimethoprim/sulfamethoxazole on lamivudine pharmacokinetics have not been studied.

Lamivudine is contraindicated in patients who are hypersensitive to any component of the product.

Several serious adverse events have been reported with lamivudine, including lactic acidosis, severe hepatomegaly with steatosis, post-treatment exacerbations of hepatitis B, pancreatitis, and emergence of viral mutants that reduce drug susceptibility and treatment response. Common side effects may include: malaise, fatigue, fever, ENT infections, sore throat, nausea, vomiting, abdominal discomfort or pain, diarrhea, muscle pain (myalgia), joint pain (arthralgia), headache, and skin rashes. Lactic acidosis and severe hepatomegaly with steatosis are rare but serious complications that require immediate medical attention.

There are no adequate and well-controlled studies of lamivudine in pregnant women. Lamivudine should be used during pregnancy only if the potential benefits outweigh the risks. Although it is not known whether lamivudine is excreted in human milk, there is a potential for adverse effects in nursing infants. Mothers receiving lamivudine should be instructed not to breastfeed.

Patients should be evaluated by a physician experienced in managing chronic hepatitis B before starting lamivudine treatment and monitored regularly during therapy.

Dose adjustment of Lamivudine is recommended based on renal function. Recommended dosing according to creatinine clearance (CrCl) is:

• CrCl ≥ 50 ml/min: 100 mg once daily
• CrCl 30–49 ml/min: 100 mg first dose, then 50 mg once daily
• CrCl 15–29 ml/min: 100 mg first dose, then 25 mg once daily
• CrCl 5–14 ml/min: 35 mg first dose, then 15 mg once daily
• CrCl < 5 ml/min: 35 mg first dose, then 10 mg once daily

Use in children: The safety and efficacy of Lamivudine for treating chronic hepatitis B in children have not been established.

Hepatic viral infections (Hepatitis B)

Store Lamivudine at a temperature below 30°C, protected from light and moisture. Keep out of reach of children.