Parasites and Protozoa and C diff Pharm Flashcards
Nematodes- drugs
- Albendazole
- Mebendazole
Cestodes- drugs
- Albendazole
- Mebendazole
- Praziquantel
Trematodes- drugs
-Praziquantel
soil-transmitted helminths
- ascaris, hookworm, trichuris
- albendazole or mebendazole- Benzimidazoles!!
Benzimidazoles- moa
bind to parasite B-tubulin- disrupt microtubule polymerization (stop mt dep processes- attachment, glucose-transport)
Mebendazole- bioavailability, distribution
- poor absorption!! low systemic exposure!!
- stays in intestinal tract!!
Albendazole- bioavailability, distribution
- modest absorption, efficient metabolism!!!- low systemic exposure
- hepatic metabolites!- so good for tissue dwelling helminths, hydatid cysts!!!
Thiabendazole
-cutaneous use only!! for larval migrans (systemic toxicity)
Mebendazole- treats what?
- enterobius vermicularis (pinworm)
- ascaris lumbricoides
- Trichuris trichiura (3 day course)
Albendazole- treats
- Necator a, Ancylostoma d (hookworm)
- Ascaris lumbricoides
- Toxocara (larval migrans)
Enterobius vermicularis (Pinworm)- drug
-Mebendazole
Necator americanus, Ancylostoma duodenale (Hookworm)- drug
-Albendazole
Ascaris lumbricoides- drug
- Albendazole
- Mebendazole
Toxocara (Larval migrans)- drug
-Albendazole
Trichuris trichiura (whipworm)- drug
- Mebendazole- *3 day course
- Albendazole
Albendazole and mebendazole- contraindications
pregnancy- teratogenic!!!
alternative nematode therapy
-pyrantel!!- hookworm, pinworm, roundworm (but not trichuris trichiura)
pyrantel- moa
- depolarizing neuromuscular blocking agent
- causes act of N-AChR- spastic paralysis!!
worm burden- heavy Ascaris infections- use what?
pyrantel!! with albendazole
can be used in pregnant pts?
-pyrantel
Ivermectin- used for?
- intestinal strongyloidiasis
- onchocerciasis- river blindness!!!
- lymphatic filariasis- Wuchereria bancrofti, Brugia malayi
Ivermectin- moa
- act glutamate-gated Cl channels- hyperpolarization- paralysis
- cannot cross BBB in mammals
- can act on GABA-gated Cl channels in humans- so contraindicated if BBB is disrupted!!
Diethylcarbamazine- used for?
- lymphatic filariasis
- loasis
Cestodes (tapeworms)- infections
- Cysticercosis
- Echinococcosis
- Taeniasis- pork, beef
- Diphyllobrothriasis- fish
drug for all adult form tapeworm infections
Praziquantel!!
- taenia solium- pork
- taenia saginata- beef
- diphyllobothrium latum- fish
drug for larval forms of tapeworm infections
Albendazole!!
- cysticercosis
- Echinococcus granulosus (Cystic hydatid dz)
Cysticercosis (taenia solium tapeworm)- neuro sx’s!!!- drug?
-Albendazole!!
cystic hydatid dz (Echinococcus granulosus)- drug?
-Albendazole!!
Schistosomiasis- drug?
-Praziquantel!!
Praziquantel- moa
- interfere with Ca homeostasis and causes flaccid paralysis in adult flukes
- causes ag’s within the parasite to be exposed to the action of host ab’s!!!
Metronidazole- treats what?
-Entamoeba histolytica (amebiasis)
-Giardia lamblia
(anaerobic!!- PFOR complex activates the metronidazole!)
treats giardiasis
-Tinidazole (resistance to metronidazole)
Metronidazole- AE’s
- metallic taste
- disulfiram-like rxn (sx’s assoc w/ alcohol intake)
E histolytica (amebiasis)- drug
- metronidazole!
- if sx- followed by a luminal amebicide to eliminate intraluminal cysts
colonization of intestine with E histolytica- drug?
-Paromomicin
C difficile- treatment?
- Metronidazole- initial choice
- Vancomycin (PO)- 1st choice for recurrence
- Fidaxomicin- ICU acquired
