Isometamidium

Isometamidium, a phenanthridium derivative (Fig. 5.7), is a veterinary drug effective for the treatment of trypanosomiasis in cattle, horses, buffaloes, and camels. It is administered by intramuscular injection at dosages in the range 0.5-2 mg/kg bw. 

In rats, isometamidium is poorly absorbed from the gastrointestinal tract, approximately 99% of an oral dose being excreted in the feces. A similar absorption/excretion profile is exhibited by homidium, one of the four major impurities of the commercial product that normally contains about 70% of pure... 

Isometamidium chloride hydrochlorate is a red powder that is readily soluble in water. A 1-2% solution is administered by deep i.m. injection at... 

Isometamidium 0.5-1 mg/kg administered by deep i.m. injection into the neck muscles and withers, divided between several injection sites, protects horses for 2-4 months against T. congolense and T. vivax. Prothidium bromide administered by deep i.m. injection 2 mg/kg protects horses for at least 3 months against T. congolense and... 

Trypanosomiasis Trypanosoma spp. Tartar emetic, suramin, quinapyra-mine, homidium chloride, dimi-nazene, isometamidium chloride. 

Isometamidium Chloride. 3-Amino-s-f3-(3-(ami-noim inomethyl )phenytj- l-triazenyl]-5.ethyl-6-phenylphett-anthridinium chloride 8-[3-(m-amidinophenyl -2-triaze-no]-3-amino-5-ethy l-6-phenylphenanlh ridinium chloride ... 

Under carefully controlled conditions the diazonium salt (358) was coupled with homidium chloride (360) to give the trypanocide isometamidium (361) Scheme 5.82.) [485, 486], Isometamidium chloride is exceptionally potent against Trypanosoma congolense [482], Its pharmacology has been reviewed [487],... 

Isometamidium resulted in frameshift mutations in Salmonella typhimurium strains TA 1537, TA 1538 and TA 98 in the presence of metabolic activation. 

Like isometamidium, it has not been tested in rodent carcinogenicity bioassays. It has been tested in teratogenicity studies in rats and although it produced maternotoxicity and embryotoxicity, there was no evidence of teratogenic effects." " ... 

To investigate the potential harmful effects of isometamidium on consumer safety, a single calf was treated with a combination of 45 mg [ " C]-iso-metamidium plus 73 mg of unlabelled drug (1 mg/kgbw isometamidium). Tissues from the calf had no detectable radioactivity and when these were fed to rats, there were no discernible effects and no adverse findings on gross examination at necropsy. 

L. Touratier, The advantage of using isometamidium for the control of animal trypanosomiasis. International Scientific Council for Trypanosomiasis Research and Control, Yaounde, Cameroon, 1979, pp. 308-316. 

L. D. Kinabo, J. A. Bogan, Q. A. McKellar and M. Murray, Relay bioavailability and toxicity of isometamidium residues a model for human risk assessment. Vet. Hum. Toxicol., 1989, 31, 417-421. 

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