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Lamivudine

Antiviral · Antiviral Agent

AntiviralAntiviral AgentATC null
CDSCO approvedSchedule H
EXCRETION
not curated
INTERACTIONS
8 major
SEVERE in our sources
PREGNANCY
(see Useful
FDA category + note
Top interactionssee all 8
  • BexaroteneSevereDatabaseDDInter
  • EmtricitabineSevereDatabaseDDInter
  • LeflunomideSevereDatabaseDDInter
  • LomitapideSevereDatabaseDDInter

Mechanism

Lamivudine (3TC) is a cytidine nucleoside analogue (2',3'-dideoxy-3'-thiacytidine) that is phosphorylated intracellularly to lamivudine triphosphate, which competitively inhibits both HIV-1 reverse transcriptase and HBV DNA polymerase. It is incorporated into the growing viral DNA chain where the absence of a 3'-hydroxyl group causes obligate chain termination. Lamivudine has a favorable safety profile but a low genetic barrier to resistance, with the M184V mutation in HIV reverse transcriptase emerging rapidly during monotherapy.

Indications

Chronic hepatitis B (initial treatment)Chronic hepatitis B in patients with decompensated liver disease (in combination with adefovir dipivoxil or tenofovir disoproxil)HIV and chronic hepatitis B (as part of highly active antiretroviral therapy, often with tenofovir disoproxil and emtricitabine)Chronic HBV hepatitis in adults and children 2 years or older (alternative agent)Indefinite treatment for patients with cirrhosisHIV in adults and children ≥3 monthschronic hepatitis BProphylaxis for HIV infection (health care workers exposed to blood by needle stick injury)HIV infection (in combination with other anti-HIV drugs, essential component of NACO first line regimens)chronic hepatitis B (first line drug)

Dosing

Adult
is given by mouth for the treatment of chronic hepatitis C infection, in double therapy with peginterferon alfa, interferon alfa, or sofosbuvir, or in triple therapy with peginterferon alfa and one protease inhibitor or sofosbuvir. Ribavirin is also effective in Lassa fever [unlicensed indication].…
Pediatric
3 mg/kg per day, maximum 100 mg/day, for children 2 to 17 years old
Renal adjustment
Dose reduction considered for patients with renal impairment

Pharmacokinetics

Half-life
5–7
Bioavailability
86–87%
Protein binding
<35%
Excretion
71% (renal, unchanged)

Contraindications

  • Monotherapy for hepatitis B (due to high rate of viral resistance)

Side effects

Common
Ear, nose, and throat infectionsSore throatDiarrheaheadachefatiguerashesnauseaanorexiaabdominal pain
Serious
  • Hepatitis flares upon abrupt discontinuation
  • Aminotransferase elevations after therapy cessation
  • neutropenia
  • headache
  • nausea
  • pancreatitis
  • rebound HBV replication
  • exacerbation of hepatitis
  • pancreatitis (rare)
  • neuropathy (rare)

Pregnancy & lactation

Pregnancy

(see Useful

Drug interactions

Bexarotene
Severe
Database

Drug interaction classified as: synergy

Source: DDInter

Emtricitabine
Severe
Database

.

Source: DDInter

Leflunomide
Severe
Database

Clinical effect not specified

Source: DDInter

Lomitapide
Severe
Database

Clinical effect not specified

Source: DDInter

Mipomersen
Severe
Database

Clinical effect not specified

Source: DDInter

Pexidartinib
Severe
Database

Clinical effect not specified

Source: DDInter

Teriflunomide
Severe
Database

Clinical effect not specified

Source: DDInter

Zalcitabine
Severe
Database

.

Source: DDInter

4 additional low-confidence interactions hidden — those rows lack a documented mechanism or management plan in our sources.

Related guidelines

Other Antiviral drugs

Ask House about Lamivudine

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Sources: KD Tripathi 7e, Goodman & Gilman 14e, Harrison 22e, BNF·Verified: 2026-05-13 · House clinical team