Lamivudine is used to treat HIV (human immunodeficiency virus) infection in adults and children. The active ingredient in Lamivudine is lamivudine. Lamivudine is a type of medicine known as an anti-retroviral. It belongs to a group of medicines called nucleoside analogue reverse transcriptase inhibitors (NRTIs).
Lamivudine does not completely cure HIV infection; it reduces the amount of virus in your body, and keeps it at a low level. It also increases the CD4 cell count in your blood. CD4 cells are a type of white blood cells that are important in helping your body to fight infection. Not everyone responds to treatment with Lamivudine in the same way. Your doctor will monitor the effectiveness of your treatment.
Do not take Lamivudine: if you are allergic to lamivudine or any ofthe other ingredients of this medicine
Class: Antiretroviral Agent, Reverse Transcriptase Inhibitor (Nucleoside).
Indications: Epivir®: Treatment of HIV infection when antiretroviral therapy is warranted; should always be used as part of a multidrug regimen (at least three antiretroviral agents)
Epivir-HBV®: Treatment of chronic hepatitis B associated with evidence of hepatitis B viral replication and active liver inflammation. Resistance develops rapidly in hepatitis B; consider use only if other anti-HBV antiviral agents with more favorable resistance patterns cannot be used
Mechanism of Action
Lamivudine must be converted intracellularly to its triphosphate form, which then competes with cytosine triphosphate for incorporation into the developing viral DNA strand. This results in chain termination and ceases viral DNA replication.
Mechanism of Resistance
Resistance to NRTIs occurs through two mechanisms; decreased incorporation of NRTIs into the viral DNA and increased excision of NRTIs from the viral DNA.
Lamivudine tablets, capsules, and oral solution dosage forms are bioequivalent. Protein binding is less than 36%. Approximately 5% is recovered in the urine as a transsulfoxide metabolite and 70% is excreted unchanged in the urine. Active tubular secretion appears to play a role in the clearance.
If you are pregnant, if you become pregnant, or are planning to become pregnant, talk to your doctor about the risks and benefits to you and your baby of taking Lamivudine. Lamivudine and similar medicines may cause side effects in unborn babies. If you have taken Lamivudine during your pregnancy, your doctor may request regular blood tests and other diagnostic tests to monitor the development of your child. In children whose mothers took NRTIs during pregnancy, the benefit from the protection against HIV outweighed the risk of side effects.
Women who are HIV-positive must not breast-feed, because HIV infection can be passed on to the baby in breast milk. A small amount of the ingredients in lamivudine can also pass into your breast milk. If you’re breast-feeding, or thinking about breast-feeding
Driving and using machines
Lamivudine is unlikely to affect your ability to drive or use machines.
How to take Lamivudine
Always take this medicine exactly as your doctor or pharmacist has told you. Check with your doctor or pharmacist if you are not sure. Swallow the tablets, with some water. Lamivudine can be taken with or without food. If you cannot swallow the tablets whole, you may crush and combine them with a small amount of food or drink, and take all the dose immediately.
Adults, adolescents and children who weigh at least 25 kg:
The recommended dose of Lamivudine is 300 mg a day. This can be taken as either one 150 mg tablet twice a day (leaving approximately 12 hours between each dose), or two 150 mg tablets once a day as advised by your doctor.
Children weighing at least 20 kg and less than 25 kg:
The recommended dose of Lamivudine is 225 mg a day. This can be given as 75 mg (half a 150 mg tablet) in the morning and 150 mg (one whole 150 mg tablet) in the evening, or 225 mg (one and a half 150 mg tablets) once a day as advised by your doctor.
Children weighing at least 14 kg and less than 20 kg:
The recommended dose of Lamivudine is 150 mg a day. This can be given as 75 mg (half a 150 mg tablet) twice a day (leaving approximately 12 hours between each dose), or 150 mg (one 150 mg tablet) once a day as advised by your doctor. An oral solution may also be available for the treatment of children over 3 months of age, or for people who need a lower dose than usual, or who can’t take tablets.
Common side effect:
- Central nervous system: Headache, fatigue, insomnia.
- Gastrointestinal: Nausea, diarrhea, abdominal, vomiting.
- Hematologic: Neutropenia.
- Neuromuscular and skeletal: Myalgia, neuropathy, musculoskeletal pain.
- Respiratory: Nasal signs and symptoms, cough, sore throat.
Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of NRTIs. Use with caution in pediatric patients who are at risk for the development of pancreatitis.