Medical term:

3tc


lamivudine

Epivir, Epivir-HBV, 3TC (CA), Heptovir (CA), Zeffix (UK)

Pharmacologic class: Nucleoside reverse transcriptase inhibitor

Therapeutic class: Antiretroviral

Pregnancy risk category C

FDA Box Warning

• Lactic acidosis and severe hepatomegaly with steatosis (including fatal cases) have occurred when drug was used alone or in combination with other nucleoside analogues.

• Epivir tablets and oral solution (used to treat human immunodeficiency virus [HIV] infection) contain higher dose of active ingredient (lamivudine) than Epivir-HBV tablets and oral solution (used to treat chronic hepatitis B). Patients with HIV should receive only dosing forms appropriate for HIV treatment.

• After Epivir discontinuation, severe acute hepatitis B exacerbations have occurred in patients co-infected with hepatitis B virus (HBV) and HIV. Monitor hepatic function closely for at least several months in these patients. If appropriate, begin anti-hepatitis B therapy.

Action

Inhibits HIV reverse transcription by viral DNA chain termination. Impedes RNA- and DNA-dependent DNA polymerase activities.

Availability

Oral solution: 5 mg/ml and 10 mg/ml in 240-ml bottles

Tablets: 100 mg, 150 mg, 300 mg

Indications and dosages

➣ HIV infection (given with other antiretrovirals)

Adults and children older than age 16: 150 mg P.O. b.i.d. or 300 mg P.O. daily

Children ages 3 months to 16 years: 4 mg/kg P.O. b.i.d. to a maximum of 150 mg P.O. b.i.d.

➣ Chronic HBV

Adults: 100 mg (Epivir-HBV) P.O. once daily

Children ages 2 to 17: 3 mg/kg (Epivir-HBV) P.O. once daily, to a maximum of 100 mg P.O. daily

Dosage adjustment

• Renal impairment

Contraindications

• Hypersensitivity to drug or its components

Precautions

Use cautiously in:

• impaired renal function, history of hepatic disease, obesity, granulocyte count below 1,000/mm3

• long-term therapy

• elderly patients

• women (especially if pregnant)

• children.

Administration

• Give with or without food.

☞ Be aware that Epivir contains 150 mg lamivudine and Epivir-HBV contains 100 mg lamivudine. Strengths are not interchangeable.

☞ Know that when given to patients with unrecognized or untreated HIV, Epivir-HBV is likely to cause rapid emergence of HIV resistance.

Adverse reactions

CNS: fatigue, headache, insomnia, malaise, asthenia, depression, dizziness, paresthesia, peripheral neuropathy, seizures

GI: nausea, vomiting, diarrhea, anorexia, abdominal discomfort, dyspepsia, splenomegaly, pancreatitis

Hematologic: anemia, neutropenia

Hepatic: hepatomegaly with steatosis

Metabolic: hyperglycemia, lactic acidosis

Musculoskeletal: muscle, joint, or bone pain; muscle weakness; myalgia; rhabdomyolysis

Respiratory: cough, abnormal breath sounds, wheezing

Skin: alopecia, rash, urticaria, erythema multiforme, Stevens-Johnson syndrome

Other: lymphadenopathy, body fat redistribution, hypersensitivity reactions including anaphylaxis; immune reconstitution syndrome

Interactions

Drug-drug. Co-trimoxazole: increased lamivudine blood level

Zalcitabine: interference with effects of both drugs

Drug-diagnostic tests. Alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, bilirubin, creatine kinase, liver function tests: increased levels

Hemoglobin, hematocrit, neutrophils: decreased levels

Patient monitoring

• Check vital signs regularly.

• Monitor CBC and platelet count frequently. Watch for evidence of bone marrow toxicity.

• Monitor blood glucose level and kidney and liver function test results.

• Assess neurologic and mental status. Report signs or symptoms of depression.

• Closely monitor obese patients, women, and patients with a history of hepatic disease; they're at increased risk for lactic acidosis and severe hepatomegaly with steatosis.

• Monitor HIV patients for co-infection with HBV (which may recur when drug is withdrawn).

☞ Monitor patients for signs and symptoms of immune reconstitution syndrome.

Patient teaching

• Tell patient he may take with or without food.

• Advise patient to minimize GI upset by eating small, frequent servings of healthy food and drinking plenty of fluids.

• Tell HIV patient that drug doesn't cure virus or prevent its transmission and that opportunistic infections may occur. Advise him to take appropriate precautions during sex.

• Teach patient how to recognize and immediately report signs and symptoms of immune reconstitution syndrome.

• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.

• Caution HIV patient not to breastfeed, because of risk of passing infection to infant.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.

McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved

lamiVUDine

(la-mi-vyoo-deen) ,

3TC

(trade name),

Epivir

(trade name),

Epivir-HBV

(trade name),

Heptovir

(trade name)

Classification

Therapeutic: antiretrovirals
Pharmacologic: nucleoside reverse transcriptase inhibitors
Pregnancy Category: C

Indications

HIV infection (with other antiretrovirals).Chronic hepatitis B infection.Part of HIV-postexposure prophylaxis with zidovudine and indinavir.

Action

After intracellular conversion to its active form (lamivudine-5-triphosphate), inhibits viral DNA synthesis by inhibiting the enzyme reverse transcriptase.

Therapeutic effects

Slows the progression of HIV infection and decreases the occurrence of its sequelae.
Increases CD4 cell counts and decreases viral load.
Protection from liver damage caused by chronic hepatitis B infection; decreases viral load.

Pharmacokinetics

Absorption: Well absorbed after oral administration (86% in adults, 66% in infants and children).
Distribution: Distributes into the extravascular space. Some penetration into CSF; remainder of distribution unknown.
Metabolism and Excretion: Mostly excreted unchanged in urine; <5% metabolized by the liver.
Half-life: Adults—3.7 hr; children—2 hr.

Time/action profile (blood levels)

ROUTEONSETPEAKDURATION
POunknown 0.9 hr†12 hr
†On an empty stomach; peak levels occur at 3.2 hr if lamivudine is taken with food. Food does not affect total amount of drug absorbed.

Contraindications/Precautions

Contraindicated in: Hypersensitivity; Lactation: Breast feeding not recommended for HIV positive mothers.
Use Cautiously in: Impaired renal function (↑ dosing interval/↓ dose if CCr <50 mL/min);Women, prolonged exposure, obesity, history of liver disease (↑ risk of lactic acidosis and severe hepatomegaly with steatosis);Coinfection with hepatitis B (hepatitis may recur after discontinuation of lamivudine); Obstetric / Pediatric: Pregnancy or children <3 mo (safety not established); Geriatric: ↓ dosage may be necessary due to age-related ↓ in renal function.
Exercise Extreme Caution in: Pediatric: Pediatric patients with a history of or significant risk factors for pancreatitis (use only if no alternative).

Adverse Reactions/Side Effects

Noted for combination of lamivudine plus zidovudine

Central nervous system

  • seizures (life-threatening)
  • fatigue (most frequent)
  • headache (most frequent)
  • insomnia (most frequent)
  • malaise (most frequent)
  • depression
  • dizziness

Respiratory

  • cough (most frequent)

Gastrointestinal

  • hepatomegaly with steatosis (life-threatening)
  • pancreatitis (↑ in pediatric patients) (life-threatening)
  • anorexia (most frequent)
  • diarrhea (most frequent)
  • nausea (most frequent)
  • vomiting (most frequent)
  • abdominal discomfort
  • ↑ liver enzymes
  • dyspepsia

Dermatologic

  • alopecia
  • erythema multiforme
  • rash
  • urticaria

Endocrinologic

  • hyperglycemia

Fluid and Electrolyte

  • lactic acidosis

Hematologic

  • anemia
  • neutropenia
  • pure red cell aplasia

Musculoskeletal

  • musculoskeletal pain (most frequent)
  • arthralgia
  • muscle weakness
  • myalgia
  • rhabdomyolysis

Neurologic

  • neuropathy (most frequent)

Miscellaneous

  • hypersensitivity reactions including anaphylaxis (life-threatening)
  • immune reconstitution syndrome

Interactions

Drug-Drug interaction

Trimethoprim/sulfamethoxazole ↑ levels (dose alteration may be necessary in renal impairment).↑ risk of pancreatitis with concurrent use of other drugs causing pancreatitis.↑ risk of neuropathy with concurrent use of other drugs causing neuropathy.Combination therapy with tenofovir and abacavir may lead to virologic nonresponse and should not be used.

Route/Dosage

HIV infection
Oral (Adults and Children >16 yr and ≥50 kg) 150 mg twice daily or 300 mg once daily.
Oral (Adults <50 kg) 2 mg/kg twice daily.
Oral (Children 3 mo–16 yr) Oral solution—4 mg/kg twice daily (up to 150 mg twice daily); Tablets—14–21 kg: 75 mg twice daily; 22–29 kg: 75 mg in AM, 150 mg in PM; ≥30 kg: 150 mg twice daily.

Renal Impairment

Oral (Adults) CCr 30–49 mL/min—150 mg once daily; CCr 15–29 mL/min—150 mg first dose, then 100 mg once daily; CCr 5–14 mL/min—150 mg first dose, then 50 mg once daily; CCr <5 mL/min—50 mg first dose, then 25 mg once daily.
Chronic Hepatitis B
Oral (Adults) 100 mg once daily.

Renal Impairment

Oral (Adults) CCr 30–49 mL/min—100 mg first dose, then 50 mg once daily; CCr 15–29 mL/min—100 mg first dose, then 25 mg once daily; CCr 5–14 mL/min—35 mg first dose, then 15 mg once daily; CCr <5 mL/min—35 mg first dose, then 10 mg once daily.
Oral (Children 2–17 yr) 3 mg/kg once daily (up to 100 mg/day).

Availability (generic available)

Epivir

Tablets: 150 mg, 300 mg
Oral solutionstrawberry-banana flavor: 10 mg/mL
In combination with: abacavir (Epzicom); zidovudine (Combivir); zidovudine and abacavir (Trizivir). See combination drugs.

Epivir-HBV

Tablets: 100 mg
Oral solutionstrawberry-banana flavor: 5 mg/mL

Nursing implications

Nursing assessment

  • Assess patient, especially pediatric patients, for signs of pancreatitis (nausea, vomiting, abdominal pain) periodically during therapy. May require discontinuation of therapy.
  • HIV: Assess patient for change in severity of symptoms of HIV infection and for symptoms of opportunistic infection during therapy.
    • Monitor patient for signs and symptoms of peripheral neuropathy (tingling, burning, numbness, or pain in hands or feet); may be difficult to differentiate from peripheral neuropathy of severe HIV disease. May require discontinuation of therapy.
  • Chronic Hepatitis B Infection: Monitor signs of hepatitis (jaundice, fatigue, anorexia, pruritus) during therapy.
  • Lab Test Considerations: Monitor viral load and CD4 levels before and periodically during therapy.
    • Monitor serum amylase, lipase, and triglycerides periodically during therapy. Elevated serum levels may indicate pancreatitis and require discontinuation.
    • Monitor liver function. May cause ↑ levels of AST, ALT, CPK, bilirubin, and alkaline phosphatase, which usually resolve after interruption of therapy. Lactic acidosis may occur with hepatic toxicity causing hepatic steatosis; may be fatal, especially in women.
    • May rarely cause neutropenia and anemia.

Potential Nursing Diagnoses

Risk for infection (Indications)

Implementation

  • Do not confuse lamivudine with lamotrigine. Do not confuse Epivir tablets and oral solution with Epivir-HBV tablets and oral solutions. Epivir Tablets and Oral Solution contain a higher dose of the same active ingredient (lamivudine) than in Epivir-HBV Tablets and Oral Solution. Epivir-HBV was developed for patients with hepatitis B and should not be used for patients dually infected with HIV and hepatitis B; use may lead to lamivudine-resistant HIV due to subtherapeutic dose.
  • Oral: May be administered without regard to food.

Patient/Family Teaching

  • Instruct patient to take lamivudine as directed, every 12 hr. Explain the difference between Epivir and Epivir-HBV to patients. Emphasize the importance of compliance with full course of therapy, not taking more than the prescribed amount, and not discontinuing without consulting health care professional. Take missed doses as soon as possible unless almost time for next dose. Do not double doses. Caution patient not to share medication with others.
    • Inform patient that lamivudine does not cure HIV disease or prevent associated or opportunistic infections. Lamivudine does not reduce the risk of transmission of HIV to others through sexual contact or blood contamination. Caution patient to use a condom during sexual contact and avoid sharing needles or donating blood to prevent spreading HIV to others. Advise patient that the long-term effects of lamivudine are unknown at this time.
    • Instruct patient to notify health care professional promptly if signs of peripheral neuropathy or pancreatitis occur.
    • Instruct patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and to consult health care professional before taking other Rx, OTC, or herbal products.
    • Emphasize the importance of regular follow-up exams and blood tests to determine progress and monitor for side effects.

Evaluation/Desired Outcomes

  • Slowing of the progression of HIV infection and its sequelae.
  • Decrease in viral load and improvement in CD4 levels in patients with advanced HIV infection.
  • Protection from liver damage caused by chronic hepatitis B infection; decreases viral load.
Drug Guide, © 2015 Farlex and Partners

3TC

Lamivudine, a nucleoside analogue reverse transcriptase inhibitor used in the treatment of HIV-1 and chronic hepatitis B.
Medical Dictionary, © 2009 Farlex and Partners

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