Heartburn and acid reflux are most commonly seen in GERD. Patients may experience a burning sensation behind the sternum, under the glabella, or in the upper abdomen, which may radiate to the neck and may be aggravated when lying down, bending over, and when intra-abdominal pressure is increased. When hot, sour or spicy food is consumed, as well as alcohol and smoking, the symptoms can be induced, and can be relieved by drinking water and taking antacids. The exact description of heartburn can often be felt as a burning sensation, a noisy feeling in the upper abdomen, or discomfort in the upper abdomen or behind the sternum. Patients with acid reflux and regurgitation often have regurgitation of stomach and esophageal contents into the pharynx and oral cavity, which gushes into the mouth without straining. Unlike vomiting and belching, the reflux is mostly undigested food, stomach acid, and can also have duodenal contents such as bile. If the regurgitant only reaches the esophagus and not the oropharynx, the patient may be unaware of it.