Can a four year old take children's pepto bismol (bismuth subsalicylate) and if so how much? she weighs 54lbs. thanks.

Depends: Regular pepto contains Bismuth Subsalicylate which is an Aspirin product linked to liver failure and brain damage in kids, a syndrome called reye syndrome. This is rare but regular pepto is not recommended for this reason. The company makes a chewable tablet with no salicylate (children's pepto)which can be used at a dose of 1 tablet for a kid of 4.