My 2 1/2 year old son accidently took one of my 10mg lisinopril?

Lisinopril: Taking one dose most likely will not cause harm. If your child is listless or lightheaded, sleepy or has a rapid heart rate take him to the ER. If he is awake and playful do not worry. Make sure all your medications are well secured and away from your child. Monitor him closely. If he hasn't swallowed the pill completely wash his mouth out. If there is any change take him to ER right away.