Lamivudine/Zidovudine Dosage & Rx Info

Lamivudine/zidovudine Generic Name & Formulations

Legal Class

General Description

Lamivudine 150mg, zidovudine 300mg; scored tabs.

Pharmacological Class

Nucleoside analogues (reverse transcriptase inhibitors).

How Supplied

Contact supplier

Manufacturer

Various generic manufacturers

Mechanism of Action

Lamivudine is a synthetic nucleoside analogue. Intracellularly, lamivudine is phosphorylated to its active 5′-triphosphate metabolite, lamivudine triphosphate (3TC‑TP). The principal mode of action of 3TC‑TP is inhibition of reverse transcriptase (RT) via DNA chain termination after incorporation of the nucleotide analogue. Zidovudine is a synthetic nucleoside analogue. Intracellularly, zidovudine is phosphorylated to its active 5′-triphosphate metabolite, zidovudine triphosphate (ZDV‑TP). The principal mode of action of ZDV‑TP is inhibition of RT via DNA chain termination after incorporation of the nucleotide analogue.

Lamivudine/zidovudine Indications

Indications

HIV-1 infection, in combination with other antiretroviral agents.

Lamivudine/zidovudine Dosage and Administration

Adults and Children

<30kg: not recommended. ≥30kg: 1 tab twice daily. Hepatic or renal impairment (CrCl <50mL/min): not recommended; use individual components.

Lamivudine/zidovudine Contraindications

Not Applicable

Lamivudine/zidovudine Boxed Warnings

Boxed Warning

Hematologic toxicity. Myopathy. Lactic acidosis and severe hepatomegaly with steatosis. Exacerbations of hepatitis B.

Lamivudine/zidovudine Warnings/Precautions

Warnings/Precautions

Risk of hematologic toxicity/bone marrow suppression; monitor CBCs esp. in advanced HIV-1 disease; interrupt dose if anemia or neutropenia occurs. Myopathy with prolonged zidovudine use. Suspend if lactic acidosis or pronounced hepatotoxicity (eg, hepatomegaly, steatosis) occurs. Not for treating chronic HBV infection; closely monitor patients co-infected with HBV and HIV for several months after stopping treatment (discontinuing therapy may exacerbate HBV infection); if appropriate, initiate anti-hepatitis B therapy may be warranted. History of pancreatitis. Monitor for lipoatrophy; use alternatives if suspected. Women. Obesity. Elderly. Pregnancy. Nursing mothers: not recommended.

Lamivudine/zidovudine Pharmacokinetics

Metabolism

Hepatic.

Elimination

Renal. Half-life: 5–7 hours (lamivudine), 0.5–3 hours (zidovudine).

Lamivudine/zidovudine Interactions

Interactions

Avoid concomitant stavudine, doxorubicin, nucleoside analogues (eg, ribavirin), sorbitol-containing products. Increased hematologic toxicity with ganciclovir, interferon alpha, ribavirin, other bone marrow suppressants or cytotoxic drugs. Monitor for treatment-associated toxicities (eg, hepatic decompensation) with interferon-alpha with or without ribavirin.

Lamivudine/zidovudine Adverse Reactions

Adverse Reactions

Headache, nausea, malaise, fatigue, nasal symptoms, diarrhea, cough; neutropenia, anemia, lactic acidosis, severe hepatomegaly with steatosis, myopathy, myositis, immune reconstitution syndrome, pancreatitis (discontinue if occurs), lipoatrophy.

Lamivudine/zidovudine Clinical Trials

See Literature

Lamivudine/zidovudine Note

Notes

Formerly known under the brand name Combivir. Register pregnant patients exposed to lamivudine by calling (800) 258-4263.

Lamivudine/zidovudine Patient Counseling