Clinical classification of antimalarial drugs:
- True causal prophylactics:
- Destroy the sporozoites before their invasion of reticuloendothelial cells.
- No such drugs are currently available.
- Causal prophylactics:
- Also called primary tissue schizonticides
- These drugs prevent the maturation of or destroy the sporozoites within the infected hepatic cells and thus preventing erythrocytic invasion.
- Eg: primaquine, pyrimethamine and proguanil.
- Also called schizonticides
- Inhibit erythrocytic schizonticides and prevent the rupture of infected erythrocytes.
- As rupture is inhibited there is freedom from rigors and pyrexia(clinical cure).
- They do not eradicate the infection.
- Relapse can occur with the stoppage of suppressive therapy in ovale and vivax species because of hypnozoites.
- The suppressive agents include
- Radical curatives:
- These drugs eradicate both erythrocytic and secondary exoerythrocytic schizogony.
- Relapse do not occur
- For radical cure of vivax infection , primaquine and proguanil are effective.
- Radical cure of falciparum malaria can be achieved with suppressives alone because of absence of secondary exoerythrocytic cycle.
- Gametocytocidal drugs:
- Chloroquine, quinine, artesunate are effective against gametocytes of all species except plasmodium falciparum.
- Primaquine is effective against falciparum species gametocytes also.
Chemical classification of antimalarial drugs:
- Cinchona alkaloids:
- Quinoline derivatives:
- Quinoline methanol
- Phenanthrene methanol
- Artemisinin compounds: