Antiprotozoal and Anthelmintic Agents

Question 1

what is the infective form of entamoeba histolytica

Answer 1

cyst

Question 2

what form of entamoeba histolytica causes symptoms

Answer 2

trophozoite

Question 3

most common cause of non-bacterial diarrhea in North America

Answer 3

Giardia Lamblia, aka beaver fever

Question 4

symptoms of trichomonas vaginalis in women

Answer 4

vaginitis and frothy, yellow discharge

Question 5

what organism is a major cause of death in AIDS patients

Answer 5

pneumocystis jirovecii

Question 6

metronidazole is DOC for what three organisms

Answer 6

e. histolytica, g. lamblia, t. vaginalis

Question 7

MOA for metronidazole

Answer 7

prodrug, reacts with reduced ferredoxin and form unstable molecules

Question 8

what should metronidazole be given with for symptomatic e. histolytica

Answer 8

luminal amebicide (paromomycin or idoquinol)

Question 9

flagyl adverse reactions

Answer 9

dysgeusia and disulfiram

Question 10

when is tinidazole used

Answer 10

when patients with e. histolytica, g. lamblia, or t. vaginalis cannot handle flagyl

Question 11

use for emetine and dehydroemetine

Answer 11

severe intestinal or systemic e. histolytica infections

Question 12

toxicites of emetine and dehydroemetine

Answer 12

cardiotoxicity, serious GI effects, and teratogenic

Question 13

treatment of asymptomatic e. histolytica

Answer 13

paromycin or idoquniol

Question 14

route of administration for iodoquinol

Answer 14

oral, poorly absorbed so remains in intestinal lumen

Question 15

toxicities of iodoquinol

Answer 15

high iodine content, severe adverse effects of the eye (optic neuritis and optic atrophy)

Question 16

paromomycin route

Answer 16

oral or cream, not absorbed so no ototoxicity or nephrotoxicity

Question 17

spectrum for paromomycin

Answer 17

amebiasis (alone, or with flagyl if symptomatic), giardiasis, t. vaginalis

Question 18

spectrum for diloxanide furoate

Answer 18

effective against luminal trophozoites

Question 19

alternative drugs for treatment of amebiasis and giardiasis

Answer 19

tetracyclines and erythromycin

must be in combo with metronidazole

Question 20

DOC for toxoplasmosis

Answer 20

pyrimethamine plus sulfadiazine

PLUS leucovorin to present bone marrow suppression

Question 21

DOC fot pneumocystis pneumonia

Answer 21

bactrim

Question 22

what is given for prophylaxis against p. jirovecii in AIDS patients

Answer 22

bactrim

Question 23

what is pentamidine effective against

Answer 23

p. jirovecii

Question 24

route of administration for pentamidine

Answer 24

IM injection for active infection

nebulizer for prophylaxis

Question 25

roundworm

Answer 25

nematodes

Question 26

tapeworm

Answer 26

cestode

Question 27

flukes

Answer 27

trematodes

Question 28

blood flukes

Answer 28

shistosomes

Question 29

roundworm DOC and 2nd choice

Answer 29

DOC: albendazole or mebendazole
Alternative: ivermectin

Question 30

flukes DOC

Answer 30

praziquantel

Question 31

tapeworm DOC

Answer 31

praziquantel

Question 32

MOA for albendazole and mebendazole

Answer 32

inhibits microtubule polymerization by binding to b-tubulin

also inhibits microtubule-dependent uptake of glucose that leads to death

Question 33

spectrum for albendazole and mebendazole

Answer 33

broad spectrum, useful for mixed roundworm infections

Question 34

adverse effects for albendazole and mebendazole

Answer 34

may be embryotoxic and teratogenic, use with caution in pregnant females

Question 35

MOA for pyrantel pamoate

Answer 35

cholinesterase inhibitor; produces depolarizing neuromuscular blockade

Question 36

MOA for ivermectin

Answer 36

paralyzes the parasite, intensifies GABA mediated transmission of signals in peripheral nerves

Question 37

praziquantel DOC

Answer 37

all species of schistosomes, effective against many cestodes and trematodes