What is the recommended dose of chloroquine (antimalarial medication) for pediatric patients?

Recommended Dosage of Chloroquine for Pediatric Patients

The recommended dose of chloroquine for pediatric patients with malaria is 10 mg/kg base (not exceeding 600 mg base) as an initial dose, followed by 5 mg/kg base at 6,24, and 36 hours, for a total dose of 25 mg/kg base over three days. 1

Dosing Regimen for Treatment of Malaria

Uncomplicated Malaria Treatment

• For treatment of uncomplicated malaria due to chloroquine-sensitive Plasmodium species, children should receive:

  • First dose: 10 mg base/kg (not exceeding 600 mg base) 1
  • Second dose: 5 mg base/kg (not exceeding 300 mg base) at 6 hours after first dose 1
  • Third dose: 5 mg base/kg at 24 hours after first dose 1
  • Fourth dose: 5 mg base/kg at 36 hours after first dose 1

• This regimen provides a total dose of 25 mg/kg chloroquine base over a 3-day period 2

Prophylaxis Dosing

• For malaria prophylaxis in children, the dose is 5 mg/kg base once weekly (not exceeding the adult dose regardless of weight) 1
• Prophylaxis should begin 2 weeks before exposure and continue for 8 weeks after leaving the endemic area 1

Administration Considerations

Weight-Based Dosing

• Pediatric dosing must be calculated by body weight to ensure appropriate therapeutic levels 1
• The pediatric dose should never exceed the adult dose regardless of weight 1

Formulation Options

• Chloroquine phosphate tablets contain 500 mg salt (equivalent to 300 mg base) 1
• For young children who cannot swallow tablets, pharmacists can prepare appropriate doses by pulverizing tablets and preparing gelatin capsules with calculated pediatric doses 2
• Mixing the powder in food or drink may facilitate administration to children 2

Safety Considerations

Potential Adverse Effects

• Standard dosing (25 mg/kg total) has minimal side effects in children 3
• Higher doses may increase risk of gastrointestinal effects like vomiting and diarrhea 4
• Chloroquine should be stored in child-proof containers out of reach of children as overdose can be fatal 2

Special Populations

• For areas with chloroquine resistance, alternative antimalarials should be considered 2
• When treating P. vivax or P. ovale infections, concomitant therapy with an 8-aminoquinoline compound is necessary for treatment of the liver stage forms 1

Alternative Administration Routes

• For children with severe malaria who cannot take oral medication:
  • Continuous infusion (0.83 mg base/kg/hour for 30 hours) or smaller, more frequent intramuscular injections (3.5 mg base/kg every 6 hours) are safer than large intermittent doses 5
  • Chloroquine given by nasogastric tube (initial dose 10 mg base/kg) is well absorbed even in comatose children 5

Regional Considerations

• In areas with high chloroquine resistance, alternative antimalarials like atovaquone-proguanil (Malarone) or mefloquine may be more appropriate 2
• Some regions have adopted higher total doses (50 mg/kg) divided over 3-6 days to overcome partial resistance, though this is not universally recommended 4, 3