GI pharmacology

What protozoan parasites cause malaria?

Plasmodium parasites

What plasmodium species cause malaria?

-Plasmodium falciparum
-Plasmodium vivax
-Plasmodium ovale
-Plasmodium malariae
-Plasmodium knowlesi

What is the most common parasite causing malaria?

Plasmodium falciparum

Which plasmodium parasites leave dormant parasites?

P. vivax, ovale and malariae

Briefly describe the cycle of the infective component of malaria:

-Sporozoites develop in the mosquito oocytes.
-These are ingested by the human.
-Sporozoites mature in the liver to form schizonts.
-Schizonts enter the blood and divide to form merozoites.
-Merozoites enter RBCs, where they use up Hb and divide, causing

What are the differences between tertian and quartan fever in malaria?

Tertian - fever on 1st and 3rd days (every two days).
Quarten - fever on 1st and 4th days (every three days).

What are the dormant form of the protozoan parasites called?

Hypnozoites

What are the stages of malaria?

1. Premonitory - lack of energy
2. Cold stage - shivering
3. Hot stage - fever
4. Sweating - fever breaks, exhausted sleep

ABCD of malaria prevention

Awareness: know the risks
Bites by mosquitoes: prevent or avoid
Comply with chemoprophylaxis
Diagnose breakthrough malaria swiftly

Example of a mosquito skin repellent

DEET

True prophylaxis of malaria is almost impossible to achieve in malaria; how does clinical prophylaxis work?

It suppresses blood parasites until the risk of liver re-infection is low.

What are anti-malarials called?

Schizonticides

Examples of rapid-acting blood schizonticides:

Quinine, chloroquine, mefloquine

What is the proposed mechanism of action for rapid-acting blood schizonticides?

They bind to haemin (breakdown product of Hb), thus accumulate in infected RBCs. Here, they inhibit haeme polymerase, causing an accumulation of haeme which is toxic to parasites.