Paper II
2023 March (Supplementary) (2010 Scheme)

Question

Chloroquine

Q63 marksShort Notes

Answer

Chloroquine is a 4-aminoquinoline blood schizonticide.

MOA: chloroquineaccumulates in the parasite’s acidic food vacuole (ion-trapped as a weak base) → inhibits haem polymerase → blocks conversion of toxic free haem (released during hemoglobin digestion) into inert haemozoin → toxic free haem accumulates and kills the parasite.

Uses: treatment of P. vivax malaria (still largely effective), chemoprophylaxis, rheumatoid arthritis/lupus (immunomodulatory property, distinct from its antimalarial mechanism).

Adverse effects: retinopathy (irreversible, dose/duration-related — periodic ophthalmologic monitoring with long-term use), pruritus (notably common in patients of West African descent), QT prolongation at high doses. Widespread resistance (via the PfCRT transporter pumping the drug out of the food vacuole) has substantially limited its use against P. falciparum.

Other Years Asked


Revise MBBS
Preview