Primaquine Phosphate

Primaquine phosphate is an 8-aminoquinoline antimalarial medication. It targets the latent liver stages (hypnozoites) of P. vivax and P. ovale to prevent relapses. It also has gametocytocidal activity against P. falciparum, helping to limit malaria transmission. Prior screening for Glucose-6-phosphate dehydrogenase (G6PD) deficiency is mandatory before prescribing primaquine, as it can cause severe, life-threatening hemolytic anemia in G6PD-deficient individuals.

Dosage by Body Weight

Dosages are expressed in terms of primaquine base (15 mg base is equivalent to 26.3 mg of primaquine phosphate). The standard pediatric dose is 0.25 mg to 0.5 mg base per kg body weight once daily for 14 days. It must be administered with food to minimize gastrointestinal side effects. G6PD status must be confirmed normal before starting treatment.

  1. Body Weight
    Below 5 kg
    Dose
    0.25 mg to 0.5 mg base/kg
    Frequency
    Once daily for 14 days
    Tracking Notes
    Safety and efficacy not fully established in infants. Must confirm G6PD-normal status. Tablet crushing and dilution required for precise dosing.
  2. Body Weight
    5-7 kg
    Dose
    1.25 mg to 2.5 mg base
    Frequency
    Once daily for 14 days
    Tracking Notes
    Administer with food. G6PD testing required before initiation. Requires careful division of tablets or specialized compounding.
  3. Body Weight
    8-10 kg
    Dose
    2 mg to 3.75 mg base
    Frequency
    Once daily for 14 days
    Tracking Notes
    Monitor closely for gastrointestinal tolerance and signs of hemolysis (dark urine, pale skin).
  4. Body Weight
    11-15 kg
    Dose
    2.75 mg to 5.6 mg base
    Frequency
    Once daily for 14 days
    Tracking Notes
    Always administer with a meal. Monitor G6PD-related parameters.
  5. Body Weight
    16-20 kg
    Dose
    4 mg to 7.5 mg base
    Frequency
    Once daily for 14 days
    Tracking Notes
    7.5 mg base corresponds to half of a standard 15 mg base tablet.

Formulation

Tablet

Purpose

Radical cure (prevention of relapse) of Plasmodium vivax and Plasmodium ovale malaria, and terminal prophylaxis of malaria.

Generic Name

Primaquine Phosphate

Branded Drug Names

Primaquine Phosphate is listed as a generic drug name. Common branded medicines that may contain the same active ingredient include:

Scheduled Drug

Yes. This medicine should be supplied or used only according to applicable prescription and regulatory requirements.

Alternatives

Disclaimer: This information is for educational purposes only. WHO references and weight bands are simplified for tracking and must not replace medical advice. Always consult with a healthcare professional before starting or changing any medication.