Epivir HBV (lamivudine) is a prescription antiviral medication specifically formulated for the treatment of chronic hepatitis B virus (HBV) infection in adults and pediatric patients. As a nucleoside reverse transcriptase inhibitor, it works by inhibiting the replication of HBV DNA, thereby reducing viral load and liver inflammation. This oral solution and tablet formulation is a cornerstone in the management of chronic HBV, aimed at suppressing viral activity, improving liver histology, and reducing the risk of long-term complications such as cirrhosis and hepatocellular carcinoma. Clinical use requires careful patient selection and monitoring under specialist supervision to optimize therapeutic outcomes and manage potential resistance.

Features

• Contains lamivudine as the active pharmaceutical ingredient
• Available in 100 mg scored tablets and a 5 mg/mL oral solution
• Specifically indicated for chronic hepatitis B virus infection
• Oral administration with or without food
• Requires prescription and specialist oversight
• Manufactured under strict pharmaceutical quality controls

Benefits

• Effectively suppresses HBV viral replication, leading to reduced viral load
• Improves liver enzyme levels (ALT normalization) and liver histology
• May delay disease progression to cirrhosis and hepatocellular carcinoma
• Generally well-tolerated with a established safety profile in appropriate patients
• Convenient once-daily dosing regimen supports adherence
• Available in pediatric formulation for treatment in children aged 2 years and older

Common use

Epivir HBV is primarily indicated for the treatment of chronic hepatitis B infection associated with evidence of viral replication and active liver inflammation or disease. It is used in both treatment-naïve patients and as part of combination therapy strategies in certain clinical scenarios. The medication is typically prescribed when there is elevated HBV DNA levels, elevated ALT levels, and/or evidence of histological liver damage. Treatment decisions should be based on comprehensive assessment including HBeAg status, viral load, liver function tests, and histological findings when available.

Dosage and direction

The recommended oral dose of Epivir HBV for adults is 100 mg once daily. For pediatric patients aged 2 to 17 years, the recommended dose is 3 mg per kg once daily, up to a maximum of 100 mg daily. The oral solution should be administered using the provided dosing syringe to ensure accurate measurement. Tablets may be taken with or without food. Dosage adjustment is required in patients with renal impairment (creatinine clearance <50 mL/min): for CrCl 30-49 mL/min: first dose 100 mg, then 50 mg daily; CrCl 15-29 mL/min: first dose 100 mg, then 25 mg daily; CrCl 5-14 mL/min: first dose 35 mg, then 15 mg daily; CrCl <5 mL/min: first dose 35 mg, then 10 mg daily.

Precautions

Treatment with Epivir HBV requires careful monitoring throughout therapy. Regular assessment of HBV DNA levels, liver function tests, and complete blood count is essential. Patients should be monitored for signs of lactic acidosis and severe hepatomegaly with steatosis, which although rare, can be fatal. Caution is advised in patients with risk factors for liver disease. Exacerbations of hepatitis may occur upon discontinuation of therapy; close monitoring for several months after stopping treatment is recommended. HIV testing should be offered before initiation and periodically during treatment, as lamivudine at the hepatitis B dose may select for HIV resistance if undiagnosed HIV coinfection exists.

Contraindications

Epivir HBV is contraindicated in patients with known hypersensitivity to lamivudine or any component of the formulation. The medication should not be used as monotherapy in patients with HIV coinfection, as subtherapeutic dosing may lead to HIV resistance development. Use with caution in patients with significant renal impairment requiring dosage adjustment. Not recommended for use in patients with known mitochondrial disorders due to risk of lactic acidosis.

Possible side effect

Common adverse reactions (≥10%) include headache, fatigue, dizziness, nausea, diarrhea, and cough. Less frequently reported effects include neutropenia, thrombocytopenia, elevated liver enzymes, pancreatitis (especially in pediatric patients), peripheral neuropathy, and insomnia. Rare but serious adverse effects include lactic acidosis with hepatic steatosis, severe acute exacerbations of hepatitis B upon discontinuation, and immune reconstitution syndrome. Musculoskeletal pain, rash, and alopecia have been reported in some patients.

Drug interaction

Lamivudine exhibits minimal metabolism and few clinically significant drug interactions. However, concomitant administration with other medications eliminated renally may require monitoring. Trimethoprim/sulfamethoxazole increases lamivudine exposure by approximately 40%; consider dosage adjustment in patients with renal impairment. No significant interactions with cytochrome P450 enzyme system. Use with other nephrotoxic agents may require increased monitoring of renal function.

Missed dose

If a dose is missed, it should be taken as soon as possible on the same day. However, if remembered near the time of the next scheduled dose, the missed dose should be skipped and the regular dosing schedule resumed. Patients should not take a double dose to make up for a missed dose. Consistent daily administration is important for maintaining antiviral efficacy and minimizing resistance development.

Overdose

There is limited experience with Epivir HBV overdose. Cases of overdose have been reported with higher doses of lamivudine (as used in HIV treatment), and were associated with no specific symptoms or only minor manifestations such as dizziness, headache, and gastrointestinal disturbances. Hemodialysis removes approximately 30% of the dose over 4 hours, but its clinical value in managing overdose is unknown. Treatment should be supportive and symptomatic, with monitoring of vital signs and laboratory parameters.

Storage

Store Epivir HBV tablets at 25°C (77°F); excursions permitted to 15-30°C (59-86°F). Keep in original container with tight closure to protect from moisture. The oral solution should be stored at 25°C (77°F); excursions permitted to 15-30°C (59-86°F). Do not freeze. Keep both formulations out of reach of children. Discard any unused oral solution 30 days after first opening the bottle. Do not use beyond the expiration date printed on the packaging.

Disclaimer

This information is provided for educational purposes only and does not constitute medical advice. Epivir HBV is a prescription medication that should be used only under the supervision of a qualified healthcare professional. Treatment decisions should be based on individual patient assessment, including thorough evaluation of liver disease status, viral markers, and potential risk factors. Patients should not adjust dosage or discontinue therapy without consulting their physician. The full prescribing information should be consulted before initiating therapy.

Reviews

Clinical studies have demonstrated that Epivir HBV treatment results in HBV DNA suppression to undetectable levels in approximately 40-50% of HBeAg-positive patients and 60-70% of HBeAg-negative patients after one year of therapy. Histological improvement has been observed in 50-60% of treated patients. Long-term studies show maintained viral suppression in responders, though resistance development increases over time, with approximately 20% of patients developing YMDD mutant HBV after one year of treatment, increasing to 70% after four years of therapy. Patient satisfaction surveys indicate appreciation for the once-daily dosing convenience, though some express concern about long-term efficacy due to resistance potential.