Antimicrobial Agents -Antiparasitics

Question 1

Does nematodes or filariae need drugs that are well absorbed? What about strongyloides stercoralis?

Answer 1

1. filiarea- think they are delivered by vector in blood so need systemic meds
2. nematode but needs well-absorbed drugs

Question 2

Is mebendazole well absorbed? albendazole? Is thiabendazole?

Answer 2

1. No
2. yes with a fatty meal
3. well absorbed

Question 3

Which benzimidazole is not well tolerated? Which benzimidazole is contraindicated in pregnancy?

Answer 3

1. Thiabendazole

2. All of them

Question 4

What do we treat ascaris lumbricoides and hookworms with and what length of Tx?

Answer 4

1. Albendazole- single dose

2. Mebendazole- three days

Question 5

What do treat enterobius vermicularis with and what length of Tx?

Answer 5

1. Albendazole- single dose repeated in 2 weeks

2. Mebendazole- single dose repeated in 2 weeks

Question 6

What do we treat strongyloides stercoralis with and length of Tx?

Answer 6

1. Albendazole- 7days
2. Thiabendazole- 1-2 days
3. Ivermectim- 2 days

Question 7

Does diethylcarbamazine treat adult filariae? What is it not recommended for?

Answer 7

1. no just microfilariae

2. onchocerca volvulus- adverse reaction for dying larva- Mazzotti reaction

Question 8

Does ivermectin treat adult filariae? What is the T1/2? Are adverse reactions more or less than diethylcarbamazine?

Answer 8

1. No just microfilariae
2. 12 hours
3. less severe

Question 9

With the antifilarial agents, what are the inflammatory response and side effects due to?

Answer 9

antigens from the dying parasites

Question 10

What treats dirofilaria immitis dog heart worm?

Answer 10

ivermectin

Question 11

What is the drug of choice for elephantiasis whether it be wuchereria bancrofti or brugaria malayi?

Answer 11

Diethylcarbamazine

Question 12

What is the treatment of choice for onchocerca volvulus? Loa Loa?

Answer 12

1. Ivermectin

2. Diethylcarbamazine

Question 13

What is the only cestode that we know that humans are only the intermediate host for and not definitive host?

Answer 13

1. Echninococcus granulosus [taenia solium too but they are also definitive host]

Question 14

Does praziquantel have a long half life? does it get in CSF?

Answer 14

1. yes very long- single dose is often possible

2. Yes 15-20 % of serum concentration

Question 15

Is niclosamide absorbed well?

Answer 15

No-absorbed poorly

Question 16

What is given to all cestodes with tissue cyst stages outside the GI tract?

Answer 16

Albendazole

[(25% in echinococcal cysts; 40-50% in CSF)]

Question 17

Prazinquantel is usually a one time treatment. When is it not?

Answer 17

1. Taenia solium cystercosis

Question 18

What is used to treat the sheep liver fluke, Fasciola hepatica?

Answer 18

Biothionol

Question 19

What are the 2 problems with treatment of malaria?

Answer 19

Problem #1: Drug resistance of P. falciparum isolates in many geographic
regions.
Problem #2: Resista`nce of hypnozoite (persistent liver) stage to many
antimalarials, resulting in relapse of P. vivax or P. ovale disease.

Question 20

When are quinoline antimalarials active?

Answer 20

Against intraerythrocytic stages

Question 21

What is the T1/2 of mefloquine?

Answer 21

14 days

Question 22

What is quinine sulfate used in combination with?

Answer 22

tetracycline or doxycycline

Question 23

What drug eradicates hypnozoites?

Answer 23

primaquine

Question 24

DOES ARTEMESININS HAVE A LONG HALF LIFE?

Answer 24

No, short

[co-artemether is the drug of choice for presumptive self-treatment of malaria]

Question 25

What does halofantine cause?

Answer 25

fatal cardiac conduction abnormalities

Question 26

What does amodiaquine cause?

Answer 26

agranulocytosis in travelers

Question 27

When would we not use mefloquine, malarone, or doxycyline for malaria prophylaxis?

Answer 27

When chloroquine will suffice in CG sensitive P. falciparum regions

Question 28

What do we use to treat protozoa living in anaerobic environments?

Answer 28

Metronidazole

Entamoeba histolytica, Giardia lamblia, Trichomonas vaginalis

Question 29

Is paromomycin absorbed well?

Answer 29

No it is poorly absorbed

Question 30

What is the only agent for cryptosporidium? what is the mech.?

Answer 30

1. nitazoxanide [also can be used for resistant giardia]

2. Ferrodoxin oxidoreductase