Pepto-Bismol is an over-the-counter medication used to treat various digestive issues, including nausea, heartburn, indigestion, upset stomach, and diarrhea. Its active ingredient, bismuth subsalicylate, works by coating the stomach lining and reducing inflammation. The medication is typically available in liquid form or chewable tablets and is known for its distinctive pink color. Always consult a healthcare professional before using it, especially for prolonged symptoms.