Antiparasitic Agents

Question 0

Drugs used to tx malaria

Answer 0

Artemether/lumefantrine
Chloroquine
Primaquine

Question 1

Malarial prophylaxis

Answer 1

Chloroquine

Primaquine

Question 2

Antimalarial schinzonticides blood stage: clinical cure

Answer 2

Chloroquine

Artemisinins

Question 3

Antimalarial schinzonticides liver stage, radial cure:

Answer 3

Primaquine

Cure of relapsing malaria

Question 4

Blood stage Antimalarials are ______ against liver stage parasites

Answer 4

Ineffective

Question 5

2 agents who also have gametocidal activity, no clinical benefit but disrupts transmission

Answer 5

Artemether

Primaquine

Question 6

Chloroquine

Answer 6

Antimalarial
Weak base that becomes trapped in acidic parasite food vacuoles, accumulates in infected RBC
-digestion of hemoglobin liberates heme which is toxic to the parasite

Question 7

Chloroquine resistance due to

Answer 7

Mutated vacuolar efflux transporter (PfCRT)

Question 8

Chloroquine beneficial for …

Answer 8

Treating pregnant women

Question 9

Chloroquine adverse rxns

Answer 9

Generally well tolerated with prophylaxis

In doses for clinical cure-pruritis, HA, GI effects, cardiovascular toxicity

Question 10

Artemether

Answer 10

Antimalarial
Derived from Chinese plant qinghao
Not useful for prophylaxis

Question 11

Artemether therapeutic use and adverse rxns

Answer 11

Used in combo with lumefantrine to slow resistance
First line oral tx of MDR falciparum malaria

Neurotoxicity
Potential embryotoxicity

Question 12

Primaquine

Answer 12

Antimalarial - used in the liver stage
Used with chloroquine to achieve clinical and radical cure
Terminal prophylaxis after travel to endemic areas (vivas/ovale)

Question 13

Primaquine adverse rxns

Answer 13

Induces hemolytic anemia in G6PD deficiency
Can’t use in pregnant women,

Makes it hard to use in endemic areas

Question 14

Metronidazole (antiprotazoal)

Answer 14

Treats systemic protozoans 
Used for:
1) amebiasis - given w/ luminal amebicide (metronidiazole levels low in GI tract
2) giardiasis
3) trichomoniasis

Question 15

Paromomycin

Answer 15

Luminal antiprotazoal agent
Aminoglycoside that binds to 30s ribosomal subunit
Not absorbed from GI tract so not for systemic infections

Question 16

Paromomycin therapeutic uses

Answer 16

Alone - asymptomatic amebiasis
In combo w/metronidazole for amebic colitis/dysentery

1st trimester pregnant females being tx for giardiasis

Question 17

Albendazole

Answer 17

Antihelminthic (parasitic worms)
Inhibits polymerization of parasitic tubulin, preventing formation of cytoplasmic micro tubules, disrupts nematode motility and DNA replication

Question 18

Albendazole uses and effects

Answer 18

Cestode infections
Roundworm
Pinworms

Teratogenic
Liver toxicity with long term use

Question 19

Praziquantel

Answer 19

Increases permeability of Trematode and Cestode cell membranes to Ca = paralysis, dislodgement and death

Drug of choice for schistosomiasis

Question 20

Pyrantel pamoate

Answer 20

Depolarizing neuromuscular blocking agent

Persistant activation of parasite nicotinic ACh receptors and inhibition of AChE - spastic paralysis of worms

Available OTC

Question 21

Ivermectin

Answer 21

Immobilization of worms by tonic muscle paralysis

Cl- channels (glutamate-gated) only found in invertebrates
= hyperpolarization of cell membrane

Question 22

Ivermectin use

Answer 22

Used in veterinary medicine to tx infections by nematodes and arthropods (insects, ticks, fleas, mites)

River blindness (onchocerciasis) in humans -mazzotti rxn from dying worms