system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What is the protective pink liquid that YouTubers often drink before eating something extremely spicy and how does it work?
gpt
Pepto-Bismol

Bismuth subsalicylate, sold generically as pink bismuth and under the brand names Pepto-Bismol and BisBacter, is an antacid medication used to treat temporary discomforts of the stomach and gastrointestinal tract, such as nausea, heartburn, indigestion, upset stomach, and diarrhea.

So for the 5 year old explanation, it is medicine that coats your stomach to protect it against spicy foods and other bad things.