Antimicrobial Agents -Antiparasitics Flashcards
Does nematodes or filariae need drugs that are well absorbed? What about strongyloides stercoralis?
- filiarea- think they are delivered by vector in blood so need systemic meds
- nematode but needs well-absorbed drugs
Is mebendazole well absorbed? albendazole? Is thiabendazole?
- No
- yes with a fatty meal
- well absorbed
Which benzimidazole is not well tolerated? Which benzimidazole is contraindicated in pregnancy?
- Thiabendazole
2. All of them
What do we treat ascaris lumbricoides and hookworms with and what length of Tx?
- Albendazole- single dose
2. Mebendazole- three days
What do treat enterobius vermicularis with and what length of Tx?
- Albendazole- single dose repeated in 2 weeks
2. Mebendazole- single dose repeated in 2 weeks
What do we treat strongyloides stercoralis with and length of Tx?
- Albendazole- 7days
- Thiabendazole- 1-2 days
- Ivermectim- 2 days
Does diethylcarbamazine treat adult filariae? What is it not recommended for?
- no just microfilariae
2. onchocerca volvulus- adverse reaction for dying larva- Mazzotti reaction
Does ivermectin treat adult filariae? What is the T1/2? Are adverse reactions more or less than diethylcarbamazine?
- No just microfilariae
- 12 hours
- less severe
With the antifilarial agents, what are the inflammatory response and side effects due to?
antigens from the dying parasites
What treats dirofilaria immitis dog heart worm?
ivermectin
What is the drug of choice for elephantiasis whether it be wuchereria bancrofti or brugaria malayi?
Diethylcarbamazine
What is the treatment of choice for onchocerca volvulus? Loa Loa?
- Ivermectin
2. Diethylcarbamazine
What is the only cestode that we know that humans are only the intermediate host for and not definitive host?
- Echninococcus granulosus [taenia solium too but they are also definitive host]
Does praziquantel have a long half life? does it get in CSF?
- yes very long- single dose is often possible
2. Yes 15-20 % of serum concentration
Is niclosamide absorbed well?
No-absorbed poorly
What is given to all cestodes with tissue cyst stages outside the GI tract?
Albendazole
[(25% in echinococcal cysts; 40-50% in CSF)]
Prazinquantel is usually a one time treatment. When is it not?
- Taenia solium cystercosis
What is used to treat the sheep liver fluke, Fasciola hepatica?
Biothionol
What are the 2 problems with treatment of malaria?
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.
When are quinoline antimalarials active?
Against intraerythrocytic stages
What is the T1/2 of mefloquine?
14 days
What is quinine sulfate used in combination with?
tetracycline or doxycycline
What drug eradicates hypnozoites?
primaquine
DOES ARTEMESININS HAVE A LONG HALF LIFE?
No, short
[co-artemether is the drug of choice for presumptive self-treatment of malaria]
What does halofantine cause?
fatal cardiac conduction abnormalities
What does amodiaquine cause?
agranulocytosis in travelers
When would we not use mefloquine, malarone, or doxycyline for malaria prophylaxis?
When chloroquine will suffice in CG sensitive P. falciparum regions
What do we use to treat protozoa living in anaerobic environments?
Metronidazole
Entamoeba histolytica, Giardia lamblia, Trichomonas vaginalis
Is paromomycin absorbed well?
No it is poorly absorbed
What is the only agent for cryptosporidium? what is the mech.?
- nitazoxanide [also can be used for resistant giardia]
2. Ferrodoxin oxidoreductase
