antiparasitics Flashcards
nitroimidazoles –> metronidazole
use: GET GAP on the Metro
giaria, entamoeba, trichomonas, gardnerella vaginalis, anaerobes (below the diaphragam- bacteroides, c.diff), H. pylori
MOA/ toxicity of metro
MOA= generation of free radicals that create cytotoxic intermediates –> inhibit DNA synth
toxicity= disulfram like reaction, metallic taste, ha, nausea
what drugs are related to metro?
nitazoxinide –> cryptosporidiosis
tinidazole –> longer t1/2, better tolerated
paramycin - use, moa, tox
- aminoglycoside abx
- use: entamoeba histolytic, leishmania donovani, giardia
- MOA= binds30s ribosome –> inhibits protein synthesis
- concentrates in gut
- minimal toxicity
t/f: metronidazole and paromycin are bactericidal?
true.
pentamidine - use
treatment/ proph for PCP in patients with SULFA allergies
pyrimethamine - use, moa
anti-folate –> impairs DNA synth
use: malaria, toxo
benzimidazoles- use
mebendazole, albendazole
-use: nematodes –> ascaris, necator (hookworm), enterobius (pinworm, trichuriasis (whipworm); cestobes –> echinococcus, taenia solium
when would you use albendazole for taenia solium?
in setting of neuroxystecercosis
MOA of benzimidazoles
inhibits MT assembly
- binds interface of alpha beta tubulin dimer
- selectively binds to parasite tubulin
- *widespread resistance
pyrantel pamoate - use, moa
use= nematodes –> roundworm and hookworm
MOA= ACh receptor agonist – causes spastic paralysis of worms, which is pretty cool if you think about it.
Praziquentel - use, moa, CI
use: cysticercosis (pork worm), echinococcus (cystic hydatid dz), flukes
MOA= ca++ ionophore –> induce paralysis, detachment and excretion
- causes tegmental damage
- activates host immune system
can cause permanent damage in neurocysticercosis!!!!
drugs used in malaria are….?
quinolones
quinine
atovaquone with proguanil
artemisin
what is the MOA of quinolones/ what do they treat?
- Malaria
- MOA= acts again erythrocytic stage of infx, blocks detoxification of heme (hematin to hematazoin) via heme polymerase –> build up of heme is toxic to parasite
***falciparum evolved efflux pump resistance
quinolones by use/ toxicity
chloroquine= all but falciparum -toxicity= retinopathy, pruritis, haptotoxicity, cardiac do
primaquine= hypnozoites in ovale/vivax
-EXCLUDE G6PD
mefloquine= used in chloroquine resistance regions
-psychotic side effects
what malaria drug is used as prophylaxis? in who?
mefloquine
pregnant mamas against falciparum/ vivas
quinine- moa, tox
- CURE of erythrocytic stages of chloroquine resistant and MDR falciparum
- MOA= inhibits paraisde feeding mech, generates oxidative stress
- tox= cinchonism, stim pancreatic beta cells, hypoTN
- exclude G6PD
- CI in pregnancy
whats cinchonism again?
= visual dysfx, tinnitus, n/v
what is quinine also/ maybe better known as?
class Ia anti-arhythmic
atovaquone + proguanil - use, moa
drug resistance falciparum, PCP pneumonia, babesiosis
atovaquone= blocks ETC of p falciparum
proguanil = inhibits parasitve DHFR, potentiates mitochondiral toxicity of atovaquone
artemisinin- use, moa
use: fastest parasite clearance of all antimalarials
- kills blood stages of ALLLLL plasmodium species
- combine with other drugs to prevent resistance
moa= binds iron, breakfs down peroxide bridges –> free radicals
