3rd long

• True or false.

  Antihelminthics are classified based on the helminths they affect as well as the mechanism of action

  True
• True or false

  Newer drugs have broader spectrum of activity, affecting different species of worms (roundworms, tapeworms and flukes

  True
• against roundworms

  Anti nematodal
• against cestodes

  anti cestodal
• against flukes

  anti trematodals
• kill larval stages of the worm

  larvicidal
• inactivate the egg of the worm

  ovicidal
• kill the adult stage of the worm

  adulticide
• is the prototype of BZD, which is much less potent than other BZDs

  Thiabendazole
• a pro-BZD that is converted to fenbendazole and oxfendazole in animals

  febantel
• inhibit microtubule synthesis in nematode cells by interfering with polymerization of βtubulins

  Benzimidazole
• if the animal is in the first one-third of pregnancy

  Care should be exercised for some of the BZDs (albendazole)
• this drug is safe for animals because it does not affect microtubule synthesis in animal cells

  Benimidazole
• in ruminants this drugs are effective against major GI worms (in both the adult and larval stages)

  Albendazole, Fenbendazole, oxfenbendazole
• in ruminants

  Albendazole, fenbendazole, and oxfendazole are effective against lungworms
• In horses

  these are effective against strongyles, but have limited activity against immature strongyles

  Fenbendazole, oxfendazole, oxibendazole
• in horses

  Fenbendazole, oxfendazole, and oxibendazole are Not effective against migrating larvae of Strongylus vulgaris and S. edentatis, need elevated, multiple doses to treat these parasites
• FOO in horses are effective against Oxyuris, Trichostrongylus, and Parascaris.
• FOO in horses has limited activity against Strongyloides Habronema, and Dictyocaulus; and thus may need elevated doses to treat these parasites
• FOO in horses are not effective against Gasterophilus
• in swine

  this drug is Effective against Ascaris, Oesophagostomum, Hyostrongylus, Trichuris, Metastrongylus, and Stephanurus.

  Fenbendazole
• true or false fenbendazole in swine kills both adults and larvae (l3 and l4)

  True
• in dog and cats

  this drugs are effective against ascarids, hookworms, and whipworms in both adult and larva forms

  Fenbendazole and febantel
• this drug has ovicidal activity on nematodes

  Benimidazole
• These agents are generally safe, although albendazole may be teratogenic and embryotoxic
• •BZDs may be toxic to liver and bone marrow in dogs, particularly at high doses.
• this drug paralyzes worms by selectively activating nematode nicotinic acetylcholine (ACh) receptors, allowing entry of Na+, Ca2+, for excessive body muscle contraction, and thus induces paralysis

  Levamisole
• Ruminants - Levamisole is effective against most mature GI worms and lungworms, but it has marginal activity against Strongyloides and immature GI worms
• •Pigs - It is effective against ascarids, Strongyloides, nodular worms, lungworms, and kidney worms.
• one of the most toxic anthelmintics

  levamisolee
• levamisole haslow safety margin, especially when given by injection
• Signs of levamisole poisoning include parasympathetic stimulation, convulsions, CNS depression, and asphyxia, which is primarily the result of respiratory muscle paralysis
• Coadministration of levamisole and pyrantel, another nicotine-like nematocide, increases toxicity
• true or falseAtropine can counteract levamisole-induced depolarizing blockade of skeletal muscle

  false
• this drugs paralyze worms by causing depolarizing neuromuscular blockade.

  Pyrantel and Morantel
• Horses - Pyrantel is effective against strongyles, ascarids, and pinworms, but not against bots.
• Pigs - Pyrantel is effective against ascarids, nodular worms, and stomach worms
• •Ruminants - Morantel is used as a feed additive, which is effective against stomach worms, nodular worms, and other principal intestinal worms.
• •Dogs and cats - Pyrantel is effective against all GI nematodes, but it has limited efficacy against whipworms.
• true or false

  adverse reactions of pyrantel and morantel are similar with levamisole

  true