GI Infection pharm Flashcards
C Diff treatment
vancomycin (preferred for severe infection)
methronidazole
fidaxomicin
supportive care
C Diff treatment (Vancomycin)
Preferred for severe CDI
A glycopeptide that inhibits cell wall synthesis (D-ALA_
oral vancomycin not absorbed systemically (IV has no effect)
Adverse effect is red man syndrome
C Diff treatment (metronidazole)
used for mild CDI a nitroimidazole with toxic intermediates incorporated into bacterial DNA reduced by reacting with ferredoxin Oral and IV have wide distribution including BBB Avoid alcohol metallic taste nausa peripheral neuropathy also kills flagellated pathogens
C diff treatment ( fidaxomicin
treats recurring CDI spares anaerobic colonic flora bacterial protein synthesis inhibitor, binds RNA pol given orally limited GI side effects
H pylori treatments
bismuth subslicylate
metronidazole
tetracycline (protein synthesis inhibitor)
omeprazole
entamoeba histolytica treatment
binucleated trophozoite, tetra nucleated cyst
pathogenic if RBCs in cytoplasm
metronidazole (drug of choice for extraluminal)
- eradicates intestinal and extraintestinal infection
tinidazole (better tolerated than metronidazole)
paromomycin (luminal amebicide)
lodoquinol (luminal amebicide)
must include amebicide to ensure eradication
lodoquinol
E histolytica treatment
- 90% retained and excreted unchanged
- contraindicated in its with intolerance to iodine
- neurotoxicity with prolonged exposure
Paromomycin
- protein synthesis inhibitor
- no absorption
- no effect extraintestinally
G lamblia tx
supportive with fluid
tinidazole (first line)
metronidazole
nitazoxanide
Nitazoxanide
G lamblia tx
inhibits pyruvate-ferredoxin oxidoreductase enzyme
- disrupts metabolism
prodrug - active met is tizoxanide
tinidazole
similar to metronidazole but better tolerated
tx for G lamblia and E histolytica
cryptosporidium parvum
contaminated water, day care, travelers oocysts with 4 motile sporozoites life cycle in intestinal epithelial cells self limiting life threatening in immunocompromised
cryptosporidium tx
antidiarrheal (loperamide)
nitazoxanide
paromomycin
nematode tx
albendazole mebendazole ivermectin thiabendazole pyrantel pamoate
albendazole and mebendazole
broad spectrum
inhibits microtubule synthesis, paralyzes worm
prodrug
wide distribution
few adverse effects
contraindicated in pregnancy and cirrhosis
thiabendazole
inhibits microtubule synthesis and paralyzes worm
more toxic than albendazole and mebendazole
can cause liver failure and stevens johnson syndrome
contraindicated in pregnancy, hepatic or renal disease
ivermectin
increases GABA transmission in nematode causing paralysis
contraindicated in pregnancy and when pt is taking barbituates, benzos, or valproic acid
pyrantel pamoate
neuromuscular blocking agent, causes Ach release and inhibition of AchE
paralyzes worm
poorly absorbed from GI tract, with half being recovered unchanged in feces
no adverse effects
contraindicated in liver dysfuncitons
Necator americanus and Ancylostoma duodenale tx
albendazole (primary)
mebendazole or pyrantel pamoate (secondary)
Ascaris lumbricoides tx
albendazole or mebendazole (primary)
ivermectin (alternate)
Strongyloides stercoralis tx
ivermectin (primary)
albendazole (secondary)
T. tichiura tx
mebendazole (primary)
albendazole or ivermectin (secondary)
E. vermicularis tx
albendazole, mebendazole or pyrantel pamoate (all primary)
Schistosoma tx
praziquantel
-increases cell membrane permeability to Ca resulting in paralysis
- as worm dies, immune response may mount causing fever, pruritus, rash
contraindicated in pregnancy
cestode tx
praziquantel
niclosamide
albendazole
cestodes
Taenia solium (pig) Taenia saginata (Cow) Diphyllobothrium latum (freshwater fish) echinococcus granulosus (Dog and sheep, form Hydatid cyst)
Niclosamide
not effective against hydatid cysts or cysticercosis (t.solium)
inhibits ox phos
contraindicated in pregnancy, kids under 2 or with alcohol consumption
