Is it ok to give a two year old pepto bismol (bismuth subsalicylate)?

No: Pepto-bismol has the active ingredient bismuth subsalicylate, which has been found to be safe and effective for treating “nonspecific diarrhea” in adults. However, Bismuth Subsalicylate is chemically related to Aspirin (acetylsalicylate), which can be dangerous for children. When given during a viral illness, it can cause reye’s syndrome, a rare condition that can involve serious brain damage.