Anthelmintics Flashcards
Kumar
What are vermifuges?
expel parasites from intestinal tract
What are vermicides?
kill intestinal parasite, then expel
Which 2 drugs are an exception and produce pharmacological effects?
organphosphates
levimasole
What species is levamisole used in?
ruminants and pigs
What species is praziquantel used in?
dogs, cats, horses
What species is piperazine salts used in?
monogastric
What drugs are used just for ruminants?
salicylanilides, nitroxynil, clorsulon
What drug groups are antinematodals?
Benzimidazoles, Probenzimidazoles, imidazothiazoles, tetrahydropyrimidies, organophosphates, macrocyclic lactones, piperazine compounds
What is the prodrug that is converted into benzimidazole carbamates?
probenzimidazoles (netobimin and febantel)
Which 2 BZDs are water soluble and are limited in absorption from GI tract?
albendazole
oxfendazole
What drug does netobimin get metabolized to?
albendazole
What probenzimidazole cannot be given to pregnant dogs and cats?
febantel - vercom paste and drontal plus
What drugs are under tetrahydropyrimidines?
pyrantel and morantel
What is the mode of action of tetrahydropyrimidines?
depolarazing muscular blockade
Which species eliminates pyrantel by urine while all the others by feces?
dogs
What is the methyl ester analog of pyrantel?
morantel
What parasitic infections do organophosphates treat in ruminants?
nematode parasites of abomasum and intestine
What are the antidotes for organophosphate toxicity?
atropine and pralidoxime
What are the two major groups of macrocyclic lactones?
avermectins
milbemycins
What are the 5 avermectin drugs?
abamectin, doramectin, eprinomectin, ivermectin, selamectin
What are the 2 milbemycin drugs?
milbemycin oxime and moxidectin
What is the MOA for macrocyclic lactones?
bind to glutamate gated chloride channels, inhibits GABA
What breeds are sensitive to ivermectin?
australian shepherds and collie breeds, murrah gray cattle
Which avermectin is highly effective against screw worms?
doramectin
What avermectin deposits in sebaceous glands that act as reservoirs?
selamectin
What other avermectin can be used in collies sensitive to ivermectin and also pregnant animals?
selamectin
What macrocyclic lactone can be used prophylactically for heartworm in ivermectin sensitive collies and in microfiliaria infested dogs?
milbemycin
What can happen in very heavily infested microfilaria dogs when given milbemycin? How is it treated?
shock
corticosteroids and fluids
What milbemycin drug is more lipophilic?
moxidectin
What is the MOA for piperazine compounds?
GABA receptor agonist - hyperpolarizes membrane
Why should piperazine treatments be repeated every 2 to 4 weeks?
effective more against adult stages
What animals can piperazine be used in?
monogastric species
What can piperazine be combined with to increase activity against cyathostomes?
BZD drugs
What salt form of piperazine can be given in the feed?
citrate or adipate salts
What are the CS of large doses of piperazine in dogs and cats?
emesis, diarhea, incordination, head pressing
What are the contraindications of piperazine?
chronic renal/liver dz
heavy ascarid infections (impaction)
What group does diethylcarbamazine citrate fall under?
piperazine compounds
What is the only use of diethylcarbamazine citrate?
heartworm prevention
What is the MOA of DEC?
inhibits prostaglandin synthesis in parasite
How often does DEC need to be administered?
daily
When should DEC not be used?
microfilaria positive dogs –> hypovolemic shock
What are the 2 heartworm adulticides that inhibit cell glycolysis?
thiacertarsamide sodium
melarsomine
What are nematodes?
whipworms, roundworms, ascarids
What are cestodes?
flatworms, tapeworms
What are trematodes?
flukes
What is the MOA of heartoworm adulticides?
inhibit cell glycolysis
What animals should not be given thiacertersamide sodium?
liver/kidney fxn problems
How is melarsomine better than thiacetersamide sodium?
more potent, better bioavalability
What is required after treatment for heartworm infection?
rest for 2 weeks, limited exercise for 6 weeks
What are the 3 groups of anticestodal drugs?
natural organic,
synthetic organic
benzimidazoles
What drug is effective against taenia and diplydium spp in dogs and cats?
dichlorophen
What anti cestodal drug is effective against tapeworms and rumen flukes in ruminants?
resorantel
What anticestodal drug has wide spectrum effect against adult and immature stages and some trematodes?
praziquantel
What is the MOA of praziquantel?
Calcium release from muscle cells, membrane integrity compromised, vacuolization, burst, allow WBC to go in
What is the difference between praziquantel and epsiprantel?
epsiprantel not absorbed from GIT - treats cestodes ONLY
What do regular benzimidazoles treat?
nematodes
What do substituted BZDs treat?
certain tapeworms and flukes
What are the anticestodal BZDs?
mebendazole, fenbendazole, oxfendazole, albendazole
What cestode is important in equine medicine?
anoplocephala perfoliata
What drugs are effective against anoplocephala perfoliata?
pyrantel, niclosamide, dichlorophen, mebendazole and praziquantel
What are the important trematodal infections in veterinary med?
Fasciolosis
rumen flukes
lung flukes - dogs and cats
What is bithionol sulfoxide effective against?
rumen flukes and liver flukes of ruminants
What are the groups of drugs that are antitrematodal?
bithionol sulfoxide, nitroxynil, salicylanilides, sulfonamides, benzimidazoles
What are the 3 salicylanidlide drugs?
closantel, rafoxanide, oxyclozanide
What different spectrum does oxyclozanide have?
rumen flukes
What is the MOA of salicylanilides?
uncouples oxidative phosphorylation
What drug is effective against resistant strains of Haemonchus contortus?
Closantel (also nitroxynil in sheep)
What antitrematodal is combined with levamisole to produce broad spectrum helminth activity?
oxyclozanide
What type of drug is clorsulon?
sulfonamide
What is the MOA of clorsulon?
glycolytic enzyme inhibition of F. hepatica
What 2 sulfonamides treat F. hepatica?
clorsulon and albendazole
How is clorsulon administered?
oral, SC
safe in all animals
What can treat pancreatic flukes in cats?
fenbendazole
What is triclabendazole metabolized into?
sulfoxide and sulfone derivatives
How long does triclabendazole derivatives last in the plasma?
7 days (very bound to albumin)
What is netobimin?
probenzimidazole effective against adult fulkes
Why is rafoxanide (and closantel) effective against immature flukes?
extensively plasma protein binding, persistence
What are the drugs effective against immature liver flukes only?
diamphenethid
How is diamphenethide metabolized?
deacytylation by liver enzymes to an amine metabolite effective against immature flukes
What drug is 100% effective against immature F.hepatica?
diamphenethide (treats acute fasciolosis)
What can intestinal paramphistomosis be treated with?
resorantel and bithional
What can paragonimiasis(lung fluke in dogs and cats) be treated with?
bithionol, prazi, albendazole and fenbendazole
What antihelminth drug is an immunostimulant?
levimasole
cell mediated response
What animals should not have levimasole?
horses
What animals are most antitrematodals given to?
ruminants
What drug is contraindicated in early preganancy?
BZDs (except mebendazole, fenbendazole, flubendazole and oxibendazole)
How are BZDs administered?
orally only
What does drontal plus have in it?
febantel, pyrantel pamoate, praziquantel
What 4 drugs should not be given to animals under stress or chronic disease conditions?
Dichlorvos
Organophosphates
Levimasole
Pyrantel
What does the commercial product vercom contain?
febantel and praziquantel
What animals is febantel used in?
horses, dogs, cats
What animals is netobimin used in?
ruminants
How are imidazothiazoles administered?
All 3 ways
What is the spectrum of levimasole?
GI and lung nematodes (not in horses)
What drug do you need gloves for?
levimasole
What other drugs should not be combined with levimasole?
other neuromuscular blockade drugs - pyrantel
Which pyrantel salt is well absorbed orally?
pyrantel tartrate
Which pyrantel salt reaches the lower intestine to kill pinworms?
pyrantel pamoate
