2.1 Adults – Treatment of HIV-1 Infection  
    
    
     
     
     Oral Dosing   
    
The recommended oral dose of zidovudine tablets is 300 mg twice daily in combination with other antiretroviral agents. 
 
    
   
   
   
    
    
   2.2 Pediatric Patients (Aged 4 Weeks to Less Than 18 Years)  
   
Healthcare professionals should pay special attention to accurate calculation of the dose of zidovudine tablets, transcription of the medication order, dispensing information, and dosing instructions to minimize risk for medication dosing errors. 
 
   Prescribers should calculate the appropriate dose of zidovudine tablets for each child based on body weight (kg) and should not exceed the recommended adult dose. 
 
   Before prescribing zidovudine tablets, children should be assessed for the ability to swallow tablets. If a child is unable to reliably swallow a zidovudine tablet, the zidovudine syrup formulation should be prescribed. 
 
   The recommended oral dosage in pediatric patients aged 4 weeks to less than 18 years and weighing greater than or equal to 4 kg is provided in Table 1. Zidovudine syrup should be used to provide accurate dosage when whole tablets are not appropriate. 
 
   
     
      Table 1: Recommended Pediatric Oral Dosage of Zidovudine Tablets  
      
      
 Body Weight (kg) 
 
         Total Daily Dose 
 
         Dosage Regimen and Dose 
  
        Twice Daily 
 
         Three Times Daily 
  
       4 to < 9
 
        24 mg/kg/day
 
        12 mg/kg
 
        8 mg/kg
  
       ≥ 9 to < 30
 
        18 mg/kg/day
 
        9 mg/kg
 
        6 mg/kg
  
       ≥ 30
 
        600 mg/day
 
        300 mg
 
        200 mg
  
       
   Alternatively, dosing for zidovudine tablets can be based on body surface area (BSA) for each child. The recommended oral dose of zidovudine tablets is 480 mg per m2 per day in divided doses (240 mg per m2 twice daily or 160 mg per m2 three times daily). In some cases the dose calculated by mg per kg will not be the same as that calculated by BSA. 
 
   
   
   
    
    
   2.3 Prevention of Maternal-Fetal HIV-1 Transmission  
   
The recommended dosage regimen for administration to pregnant women (greater than 14 weeks of pregnancy) and their neonates is: 
 
    
    
     
     
     Maternal Dosing  
    
100 mg orally 5 times per day until the start of labor [see Clinical Studies (14.3)]. During labor and delivery, intravenous zidovudine should be administered at 2 mg per kg (total body weight) over 1 hour followed by a continuous intravenous infusion of 1 mg per kg per hour (total body weight) until clamping of the umbilical cord. 
 
    
    
    
     
     
     Neonatal Dosing  
    
Start neonatal dosing within 12 hours after birth and continue through 6 weeks of age. Neonates unable to receive oral dosing may be administered zidovudine intravenously. See Table 2.
 
    
      
       Table 2. Recommended Neonatal Dosages of Zidovudine 
       
       
 Route 
 
          Total Daily Dose 
 
          Dose and Dosage Regimen 
  
        Oral
 
         8 mg/kg/day
 
         2 mg/kg every 6 hours
  
        Intravenous
 
         6 mg/kg/day
 
         1.5 mg/kg infused over 30 minutes, every 6 hours
  
        
    
   
   
   
    
    
   2.4 Patients with Severe Anemia and/or Neutropenia 
   
Significant anemia (hemoglobin less than 7.5 g per dL or reduction greater than 25% of baseline) and/or significant neutropenia (granulocyte count less than 750 cells per mm3 or reduction greater than 50% from baseline) may require a dose interruption until evidence of marrow recovery is observed [see Warnings and Precautions (5.1)]. 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 erythropoietin level and patient tolerance. 
 
   
   
   
    
    
   2.5 Patients with Renal Impairment  
   
In patients maintained on hemodialysis or peritoneal dialysis or with creatinine clearance (CrCl) by Cockcroft-Gault less than 15 mL per min, the recommended oral dosage is 100 mg every 6 to 8 hours [see Use in Specific Populations (8.6), Clinical Pharmacology (12.3)]. 
 
   
   
   
    
    
   2.6 Patients with Hepatic Impairment  
   
There are insufficient data to recommend dose adjustment of zidovudine tablets in patients with impaired hepatic function or liver cirrhosis. Frequent monitoring of hematologic toxicities is advised [see Use in Specific Populations (8.7)].