Chloroquine Treatment for Plasmodium Malariae Infection

Introduction to Chloroquine Dosage

• The Centers for Disease Control and Prevention recommends a total dose of 25 mg/kg chloroquine base over 3 days for uncomplicated Plasmodium malariae infection in chloroquine-sensitive areas, with adults receiving 600 mg base initially, followed by 600 mg at 24 hours, and 300 mg at 48 hours, and children receiving 10 mg/kg, 10 mg/kg, and 5 mg/kg at 0, 24, and 48 hours respectively 1

Adult and Pediatric Dosing

• For adults, the initial dose is 600 mg base, followed by 600 mg at 24 hours, and 300 mg at 48 hours, which represents approximately 25 mg/kg body weight for an average adult 1
• For children, the first dose is 10 mg base/kg body weight at hour 0, with a total cumulative dose of 25 mg base/kg over 3 days 1

Administration and Monitoring

• The ideal scenario is for all three doses to be administered under direct supervision over the 3-day period 1
• If laboratory confirmation is performed, administer the first chloroquine dose when the blood smear is obtained, and instruct the patient to return on day 2 for results 1
• If parasitemia persists beyond 3 days, obtain a repeat thick blood smear, and if parasitemia has not decreased markedly, institute alternative therapy 1

Special Populations

• Pregnant women should be treated aggressively using the standard adult regimen, as chloroquine is safe during pregnancy and should not be withheld 1

Diagnosis and Treatment Considerations

• In highly endemic areas, fever is often assumed to be P. falciparum, but P. malariae requires specific identification via blood smear as it has different treatment considerations 1
• The presence of Plasmodium on blood smears does not prove malaria is the sole cause of febrile illness, and other causes such as pneumonia, acute lower respiratory infection, or meningitis should be considered and ruled out 1