Antiparasitics Flashcards Preview

Pharmacology > Antiparasitics > Flashcards

Flashcards in Antiparasitics Deck (19):
1

Why is malaria difficult to target?

Undergoes gross changes in morphology, localisation and metabolic pathways.

2

Melarsen

Organic arsenical against trypanosomes. Inhibits lipoic-dependent and other dithiol containing Metallo-enzymes. Actively accumulated in trypanosoma.

3

Suramin

Anti-trypanosomal without toxic metal atom. Cannot cross BBB so only effective in early stages.

4

Chloroquine

Antimalarial. Inhibits the formation of hemozoin either by inhibiting polymerase or through complexation of heme.

5

Artemisinin

Anti malarial

6

Sulfadoxin

Anti malarial anti metabolite. Inhibits folate synthesis pathway. Inhibits DHPS.

7

Pyrimethamine

Anti malarial anti metabolite. Inhibits folate synthesis pathway. Inhibits DHFR.

8

Fansidar

Anti malarial anti metabolite. Inhibits folate synthesis pathway. Inhibits DHPS and DHFR. Combination drug.

9

What are helminths?

Multicellular eukaryotes such as nematodes (roundworms).

10

What are Protozoa?

Unicellular eukaryotes

11

What are the main targets of anti-helmintics?

Energy metabolism, neuromuscular coordination and micro tubule dynamics.

12

Closantel

Antihelmentic that targets energy metabolism. Uncoupled oxidative phosphorylation.

13

Clorsulon

Antihelmentic that targets energy metabolism. Inhibits glycolysis.

14

Thiobendazoles

Block microtubule dynamics in helminths. Bind to beta-tubulin in tubular dimer and cause depolymerisation. 300-400 fold lower affinity for mammalian beta-tubulin.

15

Invermectin and piperazine

Anti helminths that target neuromuscular coordination. Enhance inhibitory neurotransmission.

16

Levamisole

Anti helminths that target neuromuscular coordination. Nicotinic ACh receptor agonist that causes muscle contraction and spastic paralysis.

17

Paraherquamide

Anti helminths that target neuromuscular coordination. Nicotinic antagonist - causes flaccid paralysis.

18

Praziquantel

Broad spectrum anti helmintic that targets neuromuscular coordination. Binds to VGCa channels, causes Ca increase and sustained contraction - spastic paralysis. Also changes external surface structure facilitating antibody binding and sensitivity to immune response.

19

How does trypanosomiasis differ in its early stage and late stage?

Early stage in blood stream. Late stage penetrates CNS.