Toxicity of venalot (a mixture of coumarin and troxerutin) in the baboon.

Venalot, a mixture of coumarin and troxerutin, in the proportion 1 to 6 respectively, was given orally to baboons at dosages of 0, 100, 300 and 1000 mg/kg/day for 26 weeks. Vomiting, usually within 3 h of administration and considered to be of central origin, in addition to vomiting immediately after dosing, was noted in animals receiving 1000 mg/kg/day. At this level, collapse on several occasions in two animals, one of which died, was also observed. Another animal receiving 1000 mg/kg/day was killed for humane reasons following a period of weight loss, reduced appetite and deterioration in body condition. However, no adverse effect on body weight gain, food or water consumption, ophthalmoscopic or electrocardiographic examinations were noted in any other animals during this study. Increased levels of liver function (serum leucine amino-peptidase (LAP), and serum ornithine carbamyl transferase (OCT) were noted during the dosing period, together with slightly increased liver weights terminally for animals receiving 1000 mg/kg/day; however, as no morphological or ultrastructural changes were noted, these findings were considered to be attributable to hypertrophy.