Simethicone is an oral medication used to treat conditions related to extra gas in the stomach, according to WebMD. Some of these symptoms include belching, bloating and the feeling of pressure or discomfort.
Simethicone is also sometimes used before certain tests are performed, such as radiography of the bowels, according to Mayo Clinic. Simethicone is an over-the-counter medication available in many forms, including liquid, tablet and chewable tablet forms. While no side effects have been reported with its use, WebMD warns that some people may have an allergic reaction to it and recommends calling the doctor if a patient experiences symptoms such as dizziness, rash or trouble breathing.