Alka-Seltzer is an over-the-counter medication commonly used to relieve heartburn, indigestion, and upset stomach. It comes in effervescent tablet form, which dissolves in water to create a fizzy solution. The active ingredients typically include aspirin, citric acid, and sodium bicarbonate, which work together to neutralize stomach acid and provide relief. This product is often taken after meals or when experiencing discomfort. While effective for many, it is important to follow the recommended dosage and consult a healthcare professional if symptoms persist. Alka-Seltzer is available in various formulations, including options for cold and flu relief.