Anti-parasitic drugs

Question 1

three major types of worms

Answer 1

• nematodes
• trematodes or flukes
• cestodes or tapeworms

Question 2

this class of worms includes:

• roundworms
• threadworms
• pinworms
• hookworms

Answer 2

Nematodes

Question 3

flukes include __________in man and ______ _____ and ____in ruminants

Answer 3

• schistosoma
• fasciola hepatica and gigantica

Question 4

Taenia and Diphydium species belong to this group of worms

Answer 4

cestodes/tapeworms

Question 5

the head of the tapeworm is called the

Answer 5

scolex

Question 6

humans get tapeworms from

Answer 6

ingesting food that has been contaminated with tapeworms, often food is undercooked or eaten rare

Question 7

Human helminths include

Answer 7

• Ascaris
• Trichuris
• Stronglygloides
• Enterobius
• Ancylostroma

Question 8

the common name for ascaris

Answer 8

roundworm

Question 9

scientific name for whipworm

Answer 9

trichuris

Question 10

common name for stronglyloides

Answer 10

threadworms

Question 11

scientific name for pinworms

Answer 11

enterobius

Question 12

common name for anycyclostroma

Answer 12

hookworm

Question 13

Toxocara canis is found in this species and when transferred to man can cause the following four medical conditions:

Answer 13

Dog

• asthma - lung larvae
• epilepsy - brain larvae
• hepatitis - liver larvae
• blindness - larvae constrict blood vessels of eyes

Question 14

Ideal anti-helmintics have these 7 properties

Answer 14

1. destroy all species of worms
2. are effective against all stages of the lifecycle
3. are effective in all sites of the body
4. do not cause worms to develop resistance
5. are non-toxic to animal
6. do not have long drug residues such that animal is removed from milking for too long
7. cost effective

Question 15

Classes of anti-nematodal drugs (8)

Answer 15

1. cyanine dyes
2. piperazine & diethylcarbamazine
3. biphenium
4. imidazole
5. pyimidines
6. organophosphates
7. avermectins
8. benzimidazoles

Question 16

these antihelmintics are effective against lungworms

Answer 16

• Diethylcarbamazine
• Levamisole
• Avermectins
• thiabendazole

Question 17

which antihelmentic is good for heartworm

Answer 17

selemectin (Ivermectin)

Question 18

what is the mechanism of action of diethylcarbamazine and levamisole

Answer 18

• sensitizes lungworms to body’s immune system
• worms destroyed by macrophage

Question 19

what is the mechanism of action of many antihelmintics

Answer 19

depolarization of muscle causing spastic paralysis

Question 20

in fasciola hepatica the adult flukes live in which part of the body

Answer 20

bile duct

Question 21

Antitrematodal drugs include these 4 classes

Answer 21

1. Salicylanilides
2. substituted Phenols
3. benzimidazole
4. Diamphetide

Question 22

which of the antitrematodals has the best effectiveness against immature flukes

Answer 22

diamphetide

Question 23

what is the mechanism of action of salicylandilides and substitued phenols

Answer 23

• decouple oxidative phosphorylation
• energy is produced in the form of heat
• worm dies due to lack of nrg and hyperthermia

Question 24

what is an important characteristic of anti-trematodal drugs

Answer 24

they must be well absorbed in the GIT in order to be taken up in the liver and excreted in the bile

Question 25

immature flukes damage the ____________ while mature flukes damage_______

Answer 25

intestines

liver

Question 26

the flukes of fasciola hepatica cause hepatitis by

Answer 26

tunnelling through liver causing hemorrahage, blocking the bile duct causing jaundice and hepatitis

Question 27

most common worm in man are

Answer 27

nematodes

Question 28

nematodes include

Answer 28

roundworms, whipworms, threadworms, pinworms

Question 29

trematode infections common in these continents

Answer 29

africa

latin america

Question 30

horses commonly have nematode, trematode or cestode infections

Answer 30

nematode

Question 31

ruminants commonly have nematode, cestode or trematode infections

Answer 31

trematode