I have been prescribed with diphenhydramine as cough remedy. I was taking it One table spoon every three hours. But what has happened is that my 4 year pld cousin has missed the dose and consumed it unknowingly. I know that he should not have done that and I don’t know what I was thinking about while taking it but it has happened. I am afraid of overdose. What are the symptoms of Benadryl overdose? Is there any antidote for me?