Acute toxicity of samorin (Isometamidium chloride) in rabbits

1. Oral administration of samorin (isometamidium chloride) to rabbits in single oral doses of 6.25, 12.5, 25 and 50 mg/kg produced signs of toxicity which were dose-dependent. These were restlessness, hyperaesthesia, tremors, convulsions and finally death. 2. Post mortem examination revealed fatty change, congestion and haemorrhage in many organs. Histopathological examination of liver, brain, kidneys and lungs showed severe circulatory changes and cellular damage. Measurement of serum constituents confirmed the presence of hepatic and renal damage. 3. Samorin produced a marked fall in the erythrocyte count and the haematocrit values of all the treated rabbits, and in doses of 25 and 50 mg/kg it also increased the osmotic fragility of the erythrocytes.