"AIDS is caused by HIV, a retrovirus that attacks the immune system. The virus destroys CD4+ T cells, a type of white blood cell that's vital to fighting off infection. The number of these cells, known as a CD4+ count, is a key measure of immune s"...
RETROVIR IV (zidovudine injection) Infusion in combination with other antiretroviral agents is indicated for the treatment of HIV infection.
Maternal-Fetal HIV Transmission: RETROVIR is also indicated for the prevention of maternal-fetal HIV transmission as part of a regimen that includes oral RETROVIR beginning between 14 and 34 weeks of gestation, intravenous RETROVIR during labor, and administration of RETROVIR Syrup to the neonate after birth. The efficacy of this regimen for preventing HIV transmission in women who have received RETROVIR for a prolonged period before pregnancy has not been evaluated. The safety of RETROVIR for the mother or fetus during the first trimester of pregnancy has not been assessed (see Description of Clinical Studies).
DOSAGE AND ADMINISTRATION
Adults: The recommended intravenous dose is 1 mg/kg infused over 1 hour. This dose should be administered 5 to 6 times daily (5 to 6 mg/kg daily). The effectiveness of this dose compared to higher dosing regimens in improving the neurologic dysfunction associated with HIV disease is unknown. A small randomized study found a greater effect of higher doses of RETROVIR on improvement of neurological symptoms in patients with pre-existing neurological disease.
Patients should receive RETROVIR IV (zidovudine injection) Infusion only until oral therapy can be administered. The intravenous dosing regimen equivalent to the oral administration of 100 mg every 4 hours is approximately 1 mg/kg intravenously every 4 hours.
Maternal-Fetal HIV Transmission
The recommended dosing regimen for administration to pregnant women ( > 14 weeks of pregnancy) and their neonates is:
Maternal Dosing: 100 mg orally 5 times per day until the start of labor. During labor and delivery, intravenous RETROVIR should be administered at 2 mg/kg (total body weight) over 1 hour followed by a continuous intravenous infusion of 1 mg/kg/hour (total body weight) until clamping of the umbilical cord.
Neonatal Dosing: 2 mg/kg orally every 6 hours starting within 12 hours after birth and continuing through 6 weeks of age. Neonates unable to receive oral dosing may be administered RETROVIR intravenously at 1.5 mg/kg, infused over 30 minutes, every 6 hours. (See PRECAUTIONS if hepatic disease or renal insufficiency is present.)
Monitoring of Patients
Hematologic toxicities appear to be related to pretreatment bone marrow reserve and to dose and duration of therapy. In patients with poor bone marrow reserve, particularly in patients with advanced symptomatic HIV disease, frequent monitoring of hematologic indices is recommended to detect serious anemia or neutropenia (see WARNINGS).
Anemia: Significant anemia (hemoglobin of < 7.5 g/dL or reduction of > 25% of baseline) and/or significant neutropenia (granulocyte count of < 750 cells/mm3 or reduction of > 50% from baseline) may require a dose interruption until evidence of marrow recovery is observed (see WARNINGS). In patients who develop significant anemia, dose interruption does not necessarily eliminate the need for transfusion. If marrow recovery occurs following dose interruption, resumption in dose may be appropriate using adjunctive measures such as epoetin alfa at recommended doses, depending on hematologic indices such as serum erythropoetin level and patient tolerance.
For patients experiencing pronounced anemia while receiving chronic coadministration of zidovudine and some of the drugs (e.g., fluconazole, valproic acid) listed in Table 4, zidovudine dose reduction may be considered.
End-Stage Renal Disease: In patients maintained on hemodialysis or peritoneal dialysis (CrCl < 15 mL/min), recommended dosing is 1 mg/kg every 6 to 8 hours (see CLINICAL PHARMACOLOGY: Pharmacokinetics).
Hepatic Impairment: There are insufficient data to recommend dose adjustment of RETROVIR in patients with mild to moderate impaired hepatic function or liver cirrhosis. Since RETROVIR is primarily eliminated by hepatic metabolism, a reduction in the daily dose may be necessary in these patients. Frequent monitoring of hematologic toxicities is advised (see CLINICAL PHARMACOLOGY: Pharmacokinetics and PRECAUTIONS: General).
Method of Preparation
RETROVIR IV (zidovudine injection) Infusion must be diluted prior to administration. The calculated dose should be removed from the 20-mL vial and added to 5% Dextrose Injection solution to achieve a concentration no greater than 4 mg/mL. Admixture in biologic or colloidal fluids (e.g., blood products, protein solutions, etc.) is not recommended.
After dilution, the solution is physically and chemically stable for 24 hours at room temperature and 48 hours if refrigerated at 2° to 8°C (36° to 46°F). Care should be taken during admixture to prevent inadvertent contamination. As an additional precaution, the diluted solution should be administered within 8 hours if stored at 25°C (77°F) or 24 hours if refrigerated at 2° to 8°C to minimize potential administration of a microbially contaminated solution.
Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever solution and container permit. Should either be observed, the solution should be discarded and fresh solution prepared.
RETROVIR IV (zidovudine injection) Infusion is administered intravenously at a constant rate over 1 hour. Rapid infusion or bolus injection should be avoided. RETROVIR IV (zidovudine injection) Infusion should not be given intramuscularly.
RETROVIR IV Infusion, 10 mg zidovudine in each mL.
20-mL Single-Use Vial, Tray of 10 (NDC 0173-0107-93).
Store vials at 15° to 25°C (59° to 77°F) and protect from light.
GlaxoSmithKline Research Triangle Park, NC 27709. October 2006.This monograph has been modified to include the generic and brand name in many instances.
Last reviewed on RxList: 4/29/2009
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