Antihelminthic Drugs

Question 1

What is Taenia saginata?

Answer 1

Beef Tapeworm

Question 2

What are the flatworms?

Answer 2

T. saginata, T. solium, Diphyllobothrium latum, Hymenolepis nana, Schistosoma hematobium, S. mansoni, S. japonicum

Question 3

What is T. solium?

Answer 3

Pork Tapeworm

Question 4

What is Diphyllobothrium latum?

Answer 4

Fish Tapeworm

Question 5

How do you get T. saginata?

Answer 5

Eating undercooked meat

Question 6

How do you get T. solium?

Answer 6

Eating undercooked pork

Question 7

How do you get D. latum?

Answer 7

Eating undercooked fish

Question 8

What is the largest tapeworm?

Answer 8

Diphyllobothrium latum

Question 9

What is the main nutrient that D. latum robs from the host?

Answer 9

B12

Question 10

What is the lifecycle of T. solium and saginata?

Answer 10

1. Animals become infected by eating eggs or proglottids 2. Oncospheres hatch and penetrate intestinal walls and circulate to the muscles 3. Oncospheres develop into cysticerci in muscle 4. Cysticerci eaten by humans 5. Cysticerci grow into worms

Question 11

What causes cysticercosis?

Answer 11

Autoinfection by T. solium. Same lifecycle as normal, but simply in the human. Cysticerci develop in brain, liver, and other tissues

Question 12

What is a high risk of T. solium infection?

Answer 12

Neurocysticercosis

Question 13

What is Hymenolepis nana?

Answer 13

Dwarf Tapeworm

Question 14

What is the most common Tapeworm infection?

Answer 14

Hymenolepis nana

Question 15

How is one infected by H. nana?

Answer 15

Ingesting eggs. Humans can transmit to humans. Children predominatly infected

Question 16

What are Cestodes?

Answer 16

Tapeworms

Question 17

What are Trematodes?

Answer 17

Flukes or Schistosomes

Question 18

What does Praziquantel treat?

Answer 18

Cestode and Trematode infestations

Question 19

How does Praziquantel work?

Answer 19

It disrupts Ca2+ homeostasis, causing muscular contraction followed by spastic paralysis. Worms dislodge and die

Question 20

What is the drug of choice for all forms of schistosomiasis?

Answer 20

Praziquantel

Question 21

What does Praziquantel not kill?

Answer 21

Eggs of T. solium

Question 22

What is one of the major risks of taking Praziquantel?

Answer 22

Severe rxn to dying worms

Question 23

What are the Nematodes?

Answer 23

Necator americanus, Ancylostoma doudenale, Enterobiasis, Ascariasis, Trichuriasis, Trichinella spiralis, Filariasis, Loa loa, Anchocerca volvulus

Question 24

What are the hookworms?

Answer 24

Necator americanus and Ancylostoma doudenale

Question 25

How do hookworms infect their host?

Answer 25

Through the skin or oral ingestion

Question 26

What is the most common worm infection in the US?

Answer 26

Enterobiasis

Question 27

What is the infection cycle for Enterobiasis?

Answer 27

1. Female lays eggs on anus at night, 2. Eggs grabbed by fingers, 3. Eggs ingested

Question 28

What is the most common worm infection in the world?

Answer 28

Ascaris

Question 29

Where do ascaris reside?

Answer 29

Small Intestine

Question 30

What is the Ascaris lifecycle?

Answer 30

1. Ingested Eggs, 2. Larva hatch in SI, 3. Penetrate intestinal wall transported to lungs, 4. ~10d worms pass through lungs to trachea and are re-swallowed, 5. Return to SI

Question 31

What infection is common in tourists who vist the subtropics and the S.E. US?

Answer 31

Trichuriasis

Question 32

Where do Trichuris live?

Answer 32

Large Intestine

Question 33

What are some of the symptoms of Trichuriasis?

Answer 33

Irritation, Inflammation of colonic mucosa, abdominal pain, diarrhea, distention

Question 34

How do you get Trichuriasis?

Answer 34

Ingesting eggs in contaminated food/liquids

Question 35

Where to filaria live?

Answer 35

Lymphatics

Question 36

What organisms cause Filariasis?

Answer 36

Wuchereria bancrofti, Brugia malayi, Brugia timori, Loa Loa, Onchocerca volvulus

Question 37

How are filaria transmitted?

Answer 37

Mosquitoes

Question 38

What do filaria cause?

Answer 38

Elephantiasis

Question 39

How is Loa loa transmitted?

Answer 39

Deer Flies

Question 40

How is Onchocerca volvulus transmitted?

Answer 40

Female Blackflies

Question 41

What is the worst outcome of Loa loa infection?

Answer 41

Ocular lesions can lead to blindness

Question 42

What does Onchocerca volvulus cause?

Answer 42

River blindness

Question 43

What are the Benzimidazoles?

Answer 43

Mebendazole, Thiabendazole, Albendazole

Question 44

What is the MOA of the Benzimidazoles?

Answer 44

Bind to tubulin. Microtubules grow from the (+) end and benzimidazoles cap the microtubules, The microtubules then shorten on the (-) end

Question 45

How can you increase the absorption of benzimidazoles?

Answer 45

Eating a fatty meal

Question 46

How do you specify P.O requirements when treating luminal parasites w/ benzimidazoles?

Answer 46

Take on empty stomach

Question 47

How do you specify P.O. requirement when taking benzimidazoles for tissue infections?

Answer 47

Take w/ a fatty meal

Question 48

Which benzimidazole forms an active metabolite on hepatic metabolism?

Answer 48

Albendazole is converted to an active sulfoxide form

Question 49

Which benzimidazole is more toxic?

Answer 49

Thiabendazole; this makes it no longer preferred

Question 50

What is the drug of choice for cysticercosis?

Answer 50

Albendazole

Question 51

What is the drug of choice for pinworms, hookworms, ascariasis, trichuriasis, and strongyloidiasis?

Answer 51

Albendazole

Question 52

What is treated w/ Mebendazole?

Answer 52

Pinworms, hookworms, ascariasis, and trichuriasis

Question 53

What is Diethylcarbamazine used to treat?

Answer 53

Filariasis and loiasis

Question 54

What is the Mazzotti rxn?

Answer 54

Severe immune response to dying worms

Question 55

What does Ivermectin treat?

Answer 55

Strongyloidiasis and Onchocerciasis

Question 56

What is the MOA for Ivermectin?

Answer 56

1. Paralyzes microfilariae, 2. Intensifies GABA-mediated transmission of signals in peripheral nerves, 3. Allows host cytotoxic cells to adhere

Question 57

Does Ivermectin kill adult worms?

Answer 57

No, it only blocks progeny release

Question 58

Why are many herding breeds sensitive to Ivermectin?

Answer 58

They lack the P-glycoprotein transporter (MDR1 gene) in the brain

Question 59

What is a broad spectrum antihelminth?

Answer 59

Pyrantel pamoate

Question 60

What can Pyrantel pamoate not treat?

Answer 60

migratory stages or ova of helminths

Question 61

What is the MOA of Pyrantel Pamoate?

Answer 61

Neuromuscular blocking agent; Causes release of ACh and inhibits cholinesterase. This paralyzes worms

Question 62

How can Doxy be used to treat onchocerciasis?

Answer 62

It kills the bacterial symbiant Wolbachia which is required for the adult onchocerca worm to live