Make benadryl illegal to buy under the age 18

My daughter attempted suicide, meanwhile while she was in the hospital in the icu i was looking through her phone and seen her looking at benadryl overdose, many many kids she seen died from benadryl, so she went and bought bottles of benadryl and took them all. No ID needed no age limit nothing they just sold it to her which gave her what she was looking for (well damn near it) and that was death that being said I feel like there should be atleast an age limit on it, just like spray paint,cigarettes,alcohol or anything else.