Osteo Bi Flex Reviews Side Effects The safe dosage of Benadryl for cats is 2.2 mg/kg or 1 mg/lb two to three times a day. The recommended dosage of liquid Benadryl (12.4mg/5ml) is 0.9 ml/ kg or 0.4 ml/lb. The dose of Benadryl for felines can be increased or decreased according to the severity of […]