Overdosing signs were observed in toxicity studies conducted in healthy dogs, treated for 39 weeks at doses of around 2 times the recommended dose (25 mg masitinib), treated for 13 weeks and 4 weeks at doses of around 3 times the recommended dose (41.7 mg masitinib), and treated for 4 weeks at doses of around 10 times the recommended dose (125 mg masitinib).