Pharm of Antihelmintic and Ectoparasites Flashcards
what are the benzimidazoles
albendazole
mebendazole
thiabendazole
moa of albendazole
inhibits microtubule synthesis, and has larvicidal effects in hydatid disease, cysticercosis, ascariasis, and hook worm.
ovicidal effects in ascariasis, ancylostomiasis, trichuriasis.
absorption of albendazole
oral absorption is erratic and increases with a fatty meal. this means that you need to not have a fatty meal if intestinal (want to stay in the intestine) and YES have fatty meal if you want it to be absorbed (in the bloodstream)
ADE albendazole
increases liver enzymes, pancytopenia
MOA diethylcarbamazine (DEC)
immobilizes microfilaria and alters surface structure, used for filariases
SE of DEC
limited, depend on number of microfilaria in the blood (once they are immobile, the body can start immune system and that’s when SE are seen)
how to dose DEC
give initial low dose to reduce reaction to dying microfilariae, kills rapidly.
can only be obtained from the CDC
clearance of diethylcarbamazine
renally cleared
is a base that gets reabsorbed when the urine is alkaline
(gets stick when urine is acidic)
MOA ivermectin
induces tonic paralysis of musculature by activating glutamate-gated chloride channels and intensifying GABA mediated transmission of signals
absorption of ivermectin
rapdily absorbed and wide tissue distribution, but doesn’t cross BBB
spectrum ivermectin
broad vs roundworms (strongyloides, onchocerciasis, cutanous larvae, lymphatic filariasis, ectoparasites (scabies and lice)
ADE ivermectin
mazzotti like reaction in filarial infection
what is the mazotti like reaction?
intensity relates to microfilarial burden, basically is the immune system reacting to the filaria.
mostly mild itching, swollen tender lymph nodes that last a few days that is relieved by ASA and antihistamines
what is pyrantel pamoate
induces persistent activation of nicotinic acetylcholine receptors and spastic paralysis and is poorly absorbed
what is pyrantel pamoate effective for
pinworms, ascariasis, hookworms
how to get pyrantel pamoate?
OTC –need to take once get it then wait for the worm life cycle to kill more
MOA praziquantel
increase permeability of cell membranes to calcium and cause increased muscular activity followed by contraction and spastic paralysis.
use for praziquantel
approved for schistosomiasis and liver fluke but also against trematodes and cestodes
need to manage inflammation
what is permethrin
ectoparasite agent that interferes with sodium transport proteins causing neurotoxicity and paralysis
resistance in permethrin?
resistance due to mutations reported in bed bugs so switch to ivermectin
what is lindane
ectoparasite agent that induce neuronal hyperstimulation and eventual paralysis
ADE of lindane
limit use bc increased potential for neurotoxicity in children and adults that are under 110lbs and in pt with underlying skin disorders
