It is very likely that the presence of the balloon in the stomach will cause nausea, vomiting or abdominal pain of varying intensity for a few days after placement. Your physician will prescribe medication to help minimize these potential effects, but these side effects can possibly persist during the first week. After the first week, once you start eating regularly, side effects will be related to the quantities or types of food that you eat. You may experience bloating, belching, pain, nausea, vomiting or heartburn related to eating incorrectly.