犬糸状虫におよぼすDithiazanineの影響について

Abstract

The data given in this paper were obtained from observations on the effect of dithiazanine on canine heartworm and present some evidences for the excellent microfilaricidal activities of this compound.Dithiazanine was given orally or intravenously to dogs daily over a period of from 2 to 17 days. Elimination of microfilariae from the blood stream was demonstrated by oral administration of 40mg/kg b.i.d for 5 days, 200mg/kg in total, as well as 20 mg/kg a day for 4 days, 80mg/kg in total, 10mg/kg a day for 4 days, 40mg/kg in totaling and 5mg/kg a day for 7 days, 35mg/kg in total. However, the dosage of 2mg/kg a day for 17 days, or 34mg/kg in total, was not sufficient to eliminate the microfilariae. Intravenous administration with 0.5mg/kg a day for 2 days, 1mg/kg in total, resulted in complete elimination of the microfilariae and was superior to the oral administration method.There was no evidence for any filaricidal effect of this compound on adult worms even when test dogs were treated with such doses 4.25 to 6 times as large as the microfilaricidal dose and given a lengthy post-treatment prior to examination. However, it was demonstrated that reproduction of microfilariae was inhibited by long-term treatment; Such side-effects as vomiting, diarrhea, and anorexia were induced in dogs given a dose of 10mg/kg or more of dithiazanine by the oral route. No side-effects were observed in dogs given a dose of 5mg/kg or less by the oral, a dose of 0.5mg/kg by the intravenous route. No significant changes in hemogram, urinalysis, bromsulfalein test, and Takata's reaction were observed even in dogs which had received a considerably large dose, such as 20mg/kg a day, orally for 17 days, or such as 0.1-0.5mg/kg a day, intravenously for 18 days. From the results mentioned above, the oral administration of 5mg/kg a day or the intravenous administration of 0.5mg/kg a day appears to be a practical dosage for removing microfilariae without any side-effects.Anthelmintic activities were not demonstrable in this compound against common intestinal parasites by intravenous dosages of O. 1-0.5mg/kg a day for 18 days, or 8.4mg/kg in total. However, a daily aral dose pf 2mg/kg or more given originally for the purpose of eliminating microfilariae resulted in the elimination of whipworms and hookworms.