What are the treatment guidelines for Plasmodium (P.) vivax malaria in India?

Treatment Guidelines for P. vivax Malaria in India

Chloroquine is the first-line treatment for uncomplicated P. vivax malaria in India, followed by primaquine for radical cure to prevent relapses, with dosing based on G6PD status. 1, 2

Treatment Algorithm for Uncomplicated P. vivax Malaria

First-Line Treatment: Chloroquine

• Chloroquine phosphate is administered at a total dose of 25 mg base/kg over 3 days 1, 2:
  • Initial dose: 10 mg base/kg (not exceeding 600 mg base)
  • Second dose: 5 mg base/kg at 6 hours (not exceeding 300 mg base)
  • Third dose: 5 mg base/kg at 24 hours
  • Fourth dose: 5 mg base/kg at 36 hours 3

Anti-Relapse Treatment (Radical Cure)

• Primaquine must be administered to eliminate liver hypnozoites and prevent relapses 1, 2
• G6PD testing is mandatory before primaquine administration 4
• For G6PD normal patients: 30 mg base per day for 14 days 4
• For patients with intermediate G6PD deficiency (30-70% activity) with non-Mediterranean variant (A-): 0.75 mg base/kg weekly (maximum 45 mg) for 8 weeks with close monitoring for hemolysis 4
• Primaquine is contraindicated in:
  • Pregnant or breastfeeding women 1, 4
  • Patients with severe G6PD deficiency (<30% activity) 4
  • Mediterranean variant (B-) G6PD deficiency 4

Alternative Treatments for Chloroquine-Resistant P. vivax

• Consider artemisinin-based combination therapy (ACT) for patients from known chloroquine-resistant areas (Papua New Guinea, Indonesia, Sabah) 1
• Dihydroartemisinin-piperaquine (DHA-PPQ) is preferred if using ACT due to longer half-life of piperaquine 1
• Other ACT options include artemether-lumefantrine (AL) 1

Management of Severe P. vivax Malaria

• Intravenous artesunate is the first-line treatment for severe malaria of any species 1:
  • Dosage: 2.4 mg/kg IV at 0,12, and 24 hours, then daily for up to 7 days 1
  • Switch to oral therapy once patient improves and can take oral medication 1
• If artesunate is unavailable, quinine dihydrochloride is the second-line option 1:
  • Loading dose: 20 mg salt/kg over 4 hours
  • Maintenance: 10 mg/kg over 4 hours starting 8 hours after initiation, then every 8 hours 1
  • Switch to oral therapy as soon as possible (after at least 48 hours of IV treatment) 1

Special Considerations

• P. vivax can cause severe disease and mortality despite historically being considered "benign" 5, 6
• Monitor for hemolysis when using primaquine, especially in patients with G6PD deficiency 4
• Chloroquine resistance in P. vivax has been reported in some areas globally, necessitating alternative treatments 7, 8
• Recurrent P. vivax infections can lead to severe anemia and malnutrition, particularly in children 5
• In pregnancy, P. vivax can cause maternal anemia, miscarriage, and low birth weight 5

Monitoring and Follow-up

• Monitor for clinical improvement within 48 hours of starting treatment 1
• For patients on primaquine, monitor for signs of hemolysis (dark urine, jaundice, fatigue) 4
• Follow-up blood smears should be obtained to confirm parasite clearance 1
• Educate patients about the importance of completing the full course of primaquine to prevent relapses 1