Classes
DEA Class; Rx
Common Brand Names; Retrovir, ZDV (formerly AZT)
- HIV, NRTIs
Description
Nucleoside reverse transcriptase inhibitor (NRTI)
Used to treat HIV-1 infections and for perinatal HIV prophylaxis
Associated with hematologic toxicity and bone marrow suppression
Indications
Indicated for the treatment of human immunodeficiency virus (HIV) infection in combination with other antiretroviral agents.
Indicated for prevention of maternal-fetal HIV-1 transmission
This indication is based on dosing regimens that includes antepartum and intrapartum therapy of HIV-1 infected mothers, and also postpartum therapy of HIV-1 exposed neonates
Instruct women to continue taking their antepartum combination PO antiretroviral agents (ART) on schedule as much as possible during labor and before scheduled cesarean delivery
Discontinue intrapartum IV infusion if oral zidovudine was part of the antepartum regimen
Women receiving combination retroviral therapy with HIV RNA <50 copies/mL near delivery do not require zidovudine IV if there are no concerns related to adherence with oral ART regimen
Contraindications
Hypersensitivity
Adverse Effects
- Anemia (23% in children)
- Anorexia (11%)
- Diarrhea (17%)
- Fever (16%)
- Granulocytopenia (39% in children)
- Headache, severe (42%)
- Leukopenia (39%)
- Nausea (46-61%)
- Pain (20%)
- Rash (17%)
- Vomiting (6-25%)
- Weakness (19%)
- Malaise (8%)
- Dizziness (6%)
- Insomnia (5%)
- Somnolence (8%)
- Hyperpigmentation of nails (bluish-brown)
- Dyspepsia (5%)
- Changes in platelet count
- Paresthesia (6%)
Warnings
Vial stoppers for injection contain dry natural rubber (a latex derivative) which may cause allergic reactions in latex-sensitive individuals
Risk of severe anemia and bone marrow depression; use with caution in patients with bone marrow compromise; hemoglobin reduction may occur 2-4 weeks and neutropenia may occur 6-8 weeks after initiating therapy; monitor blood counts; dose interruption may be required in patients who develop anemia or neutropenia
Female sex and obesity may be risk factors for development of lactic acidosis and severe hepatomegaly with steatosis in patients treated with antiretroviral nucleoside analogues
Monitor CBC with differentials (patients with poor bone marrow reserve require more frequent monitoring); perform CD4 count every 3-6 months; liver function tests recommended every 6-12 months
(All NRTIs): Risk of potentially fatal lactic acidosis and severe hepatomegaly with steatosis when used alone or in combination with other antiretrovirals; suspend treatment in any patient who develops clinical or laboratory findings suggestive of lactic acidosis or hepatotoxicity (elevation of transaminase with or without hepatomegaly and steatosis may occur)
Risk of immune reconstitution syndrome if used in combination with other antiretroviral drugs; further evaluation and treatment may be required; autoimmune disorders (such as Graves’ disease, polymyositis, and Guillain-Barré syndrome) reported to occur in setting of immune reconstitution; time to onset is more variable, and can occur many months after initiation of treatment
Lipoatrophy, causing loss of subcutaneous fat, especially in the face and buttocks may occur; incidence and severity associated with cumulative exposure; may be only partially reversible improvement may take months or years after switching to regimen that does not contain zidovudine; monitor for signs of lipoatrophy and consider switching to non-zidovudine-containing regimen if lipoatrophy occurs
Myopathy and myositis with pathological changes, similar to that produced by HIV-1 disease,associated with prolonged use of therapy
Pregnancy and Lactation
Available data from the APR show no difference in the overall risk of birth defects for lamivudine or zidovudine compared with background rate for birth defects of 2.7% in the Metropolitan Atlanta Congenital Defects Program (MACDP) reference population
The Centers for Disease Control and Prevention recommend that HIV-1-infected mothers in the United States not breastfeed infants to avoid risking postnatal transmission of HIV-1 infection
Maximum Dosage
600 mg/day PO for HIV; 6 mg/kg/day IV; doses up to 1000 mg/day PO have been used.
600 mg/day PO for HIV; 6 mg/kg/day IV; doses up to 1000 mg/day PO have been used.
30 kg or more: 600 mg/day or 480 mg/m2/day PO; safety and efficacy of IV formulation have not been established; however, doses up to 480 mg/m2/day IV have been used off-label.
less than 30 kg: 18 mg/kg/day or 480 mg/m2/day PO; safety and efficacy of IV formulation have not been established; however, doses up to 480 mg/m2/day IV have been used off-label.
30 kg or more: 600 mg/day or 480 mg/m2/day PO; safety and efficacy of the IV formulation have not been established; however, doses up to 480 mg/m2/day IV have been used off-label.
9 to 29 kg: 18 mg/kg/day or 480 mg/m2/day PO; safety and efficacy of the IV formulation have not been established; however, doses up to 480 mg/m2/day IV have been used off-label.
less than 9 kg: 24 mg/kg/day or 480 mg/m2/day PO; safety and efficacy of the IV formulation have not been established; however, doses up to 480 mg/m2/day IV have been used off-label.
9 to 29 kg: 18 mg/kg/day or 480 mg/m2/day PO; safety and efficacy of the IV formulation have not been established; however, doses up to 480 mg/m2/day IV have been used off-label.
4 to 8 kg: 24 mg/kg/day or 480 mg/m2/day PO; safety and efficacy of the IV formulation have not been established; however, doses up to 480 mg/m2/day IV have been used off-label.
Neonates 35 weeks gestational age and older: 8 mg/kg/day PO; 6 mg/kg/day IV.
Premature Neonates 30 to 34 weeks gestational age: Safety and efficacy have not been established; however, doses of 4 mg/kg/day PO or 3 mg/kg/day IV for the first 2 weeks, then 6 mg/kg/day PO or 4.6 mg/kg/day IV, have been used off-label.
Premature Neonates younger than 30 weeks gestational age: Safety and efficacy have not been established; however, doses of 4 mg/kg/day PO or 3 mg/kg/day IV for the first 4 weeks, then 6 mg/kg/day PO or 4.6 mg/kg/day IV, have been used off-label.
How supplied
Zidovudine
capsule
100mg
tablet
300mg
syrup
50mg/5mL
injectable solution
10mg/mL
