Lamivudine — what it treats and why people still use it

Lamivudine (often called 3TC) is a simple, well-known antiviral used for HIV and chronic hepatitis B. It’s not flashy, but it’s cheap, usually well tolerated, and is still part of many combination regimens. If you or someone you care for is starting lamivudine, here’s the quick, useful stuff you need to know.

What lamivudine does and how it works

Lamivudine blocks a viral enzyme called reverse transcriptase. For HIV, that helps stop the virus from copying itself. For hepatitis B, it lowers viral load and reduces liver damage. It’s rarely used alone for HIV — clinicians almost always give it as part of a multi‑drug cocktail to prevent resistance.

Dosing, side effects and safety checks

Typical adult doses: for HIV the usual dose is 300 mg once daily (or 150 mg twice daily). For chronic hepatitis B the common dose is 100 mg once daily. Children get weight‑based dosing — a pediatrician will calculate it. If you have kidney problems your doctor will lower the dose or stretch the dosing interval.

Common side effects are mild: headache, nausea, tiredness, and sometimes a cough. Serious but rare problems include lactic acidosis and severe liver enlargement with fatty change. If you stop lamivudine suddenly after long use for hepatitis B, the virus can flare and cause liver damage — doctors usually plan a safe stop or switch.

Lamivudine is not heavily processed by the liver enzymes that cause most drug interactions, so it has fewer interactions than some antivirals. Still, it’s part of multi‑drug HIV regimens, so check with your prescriber or pharmacist about how it fits with other medicines you take.

Monitoring usually includes viral load and liver tests for hepatitis B, and kidney checks if you have reduced renal function. If you’re pregnant or planning pregnancy, tell your clinician — lamivudine is commonly used in pregnancy, but treatment plans are individualized.

Practical tips for taking lamivudine: take it the same time each day, don’t skip doses, and keep follow‑up blood tests. If you miss a dose, take it when you remember unless it’s near the next dose — ask your prescriber for exact instructions.

If you notice unusual symptoms like muscle pain, severe stomach pain, yellowing skin or dark urine, get medical advice quickly. These can be signs of serious side effects or liver issues.

Buying lamivudine online? Always use a licensed pharmacy that requires a prescription, shows clear contact details, and has a pharmacist you can reach. Avoid sites that sell prescription drugs without a prescription or offer unbelievably low prices. Look for reviews and third‑party verification (national pharmacy boards or recognized seals). When in doubt, ask your local pharmacist to verify the product and packaging.

Lamivudine is straightforward, but safe use depends on the right dose, the right combination of drugs, and regular monitoring. Ask questions, keep lab appointments, and never stop or change treatment without talking to your provider.