Endoparasiticides - Nematodes
- Toxocara cati
: benzimidazoles more effective than piperazine against larval stages therefore prevent fecal output for longer period. - Aleurostrongylus treatment with fenbendazole .
Drugs for Nematodes
Benzimidazoles
- Disrupt parasite energy metabolism by binding to tubulin (required for uptake of nutrients).
- Doses may need to be repeated in kittens or when treating specific infections.
- Effective against larval and adult roundworms, some also ovicidal.
- Products containing benzimidazoles or probenzimidazoles are labeled 1-BZ.
- Fenbendazole : lungworm ( Aleurostrongylus ). GI nematodes - Toxocara cati , Toxascaris leonina , Ancylostoma and Taenia spp (tapeworm) not effective against Dipylidium .
- Mebendazole : gastrointestinal nematodes, Echinococcus and Taenia . Need to treat longer if treating tapeworms.
- Praziquantel : preferred treatment for Echinococcus .
- Febantel .
Imidazothiazoles
- Nicotinic receptor agonists interfere with parasite nerve transmission → muscular paralysis and expulsion.
- Restores depressed T-cell function.
Low therapeutic index - toxic signs include salivation and muscle tremors. - Levamisole hydrochloride * : lungworms ( Aleurostrongylus abstrusus , Capillaria aerophilia ), immune stimulation, heartworm treatment (seek specialist advice). Unlicensed in cat.
Organophosphorous compounds
- Dichlorvos : roundworms, hookworms. Safer compounds are available.
Tetrahydropyrimidines
- Interfere with parasite nerve transmission → neuromuscular paralysis.
- Effective against adults and larval gastrointestinal roundworms.
- Pyrantel embonate .
Others
- Piperazine : modifies neurotransmission → relaxation and expulsion; for some roundworms, ie Toxocara , Toxascaris and Uncinaria ; little activity against larval Toxocara in kittens; ineffective against lungworms or tapeworms. Toxic in cats with overdose (muscle fasciculations, ataxia, salivation).
- Diethylcarbamazine : piperazine derivative that acts in nicotine-like manner causing paralysis. Used for heartworm prophylaxis in dogs and has ascaricide activity. Has been used to treat Spirocerea lupi at very high doses.
Sources
Publications
Refereed papers
- Recent references from PubMed .
Other sources of information
- Kunkle G (1997) An updated review of ectoparasiticide treatments in dogs and cats. Proceedings of the 7th European Association for Veterinary Pharmacology and Toxicology International Congress , Madrid, Spain. 6-10 July.
- Lynn R C (1995) Antiparasitic Drugs. In: Georgis' Parasitology for Veterinarians. 6th edn. W B Saunders, Philadelphia. pp 247-292.
- Courtney C H & Sundlof S F (1991) Veterinary Antiparasiteic Drugs. Am Assoc Vet Parasitol , University of Florida Publication SP96, Gainesville, Florida.
