A 25-year-old woman from Maharashtra presents with recurrent P. vivax malaria despite completing chloroquine treatment for acute attacks. She continues to relapse every 3 months. Which drug prevents relapse by eradicating the dormant hepatic form?
- A Chloroquine
- B Mefloquine
- C Primaquine ✓
- D Artesunate
Explanation
P. vivax and P. ovale form dormant hepatic hypnozoites that cause relapses weeks to months after the primary attack. Primaquine is the only drug active against hypnozoites (radical cure), as it is converted to active metabolites by hepatocytes. Chloroquine eliminates erythrocytic forms but has no hypnozoite activity. Mefloquine and artesunate also act on blood stages. Before prescribing primaquine, G6PD status must be checked because the drug's oxidant metabolites cause haemolysis in G6PD-deficient patients. Tafenoquine (single-dose alternative) has the same G6PD precaution.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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