Proin is available in 25 mg, 50 mg, and 75 mg chewable tablets. Dosage of proin generally depends on the body weight of the animal. However, a dose of 12.5 mg to 50 mg can be administered three times daily, depending on weight. The usual dose of Proin in dogs is 0.4-0.8 mg/pound every 12 hours. Over dosage can bring about symptoms of high blood pressure, increased heart rate, seizures, or coma. Do not increase or reduce the dosage without veterinary prescription.