Treatment of Dirofilariasis Immitis with Concentrated Fouadin

Abstract

Dirofilaria immitis, a viviparous filarial worm living in the right chambers of the heart, the pulmonary artery and its branches, is very prevalent in China, 7.7% of dogs in Canton and 27% of dogs in Peiping being infested. No cure for the parasite was known until Itagaki et al. and Wada reported some success by using sodium antimony tartrate and neostibnal respectively. “Fouadin”, a proprietary antimony compound was found to give highly satisfactory result by Philipp and by Underwood and Wright, who gave it a very thorough trial. Hays also reported favorably on a double salt of antimony. Since the salts of antimony have given promising therapeutic result, the authors began in the winter of 1934 to test the efficacy of another complex antimony compound called “Concentrated Fouadin” against this worm. A preliminary notice of the results is here given. As subjects of experiment, naturally infected dogs were employed. To have an idea of the degree of infestation, the average of at least 3 consecutive daily counts of microfilariae in 0.025 cc. of dried and dehaemoglobinized blood obtained from the ear-vein at 4 p. m., was ascertained. For treatment, 16 dogs were divided into 2 groups. To Group I comprising 10 dogs, an intramuscular injection was given daily except Sundays until the microfilariae disappeared from the peripheral blood. The initial dose varied according to the size of the animal, generally 0.5 cc. for a dog under 10 kg. and 1 cc. for one weighing between 10 and 15 kg. For subsequent injections, the dose was gradually increased with the object of pushing the drug to the limit of tolerance as rapidly as possible. The 6 dogs of Group II were also injected intramuscularly, but after the first 2 consecutive daily doses corresponding to 0.05 cc. of Concentrated Fouadin per kg. body weight the third and the following injections were given on alternate days with a dose equal to 0.10 cc. per kg. body weight until the same result was achieved.