Heartburn once in a while is common, especially after a large meal or certain trigger foods. But when acid reflux happens repeatedly or causes ongoing symptoms, it may be gastroesophageal reflux disease, commonly called GERD. GERD can cause burning in the chest, sour taste, regurgitation, cough, throat irritation, nausea, or trouble sleeping. Many cases can be managed with lifestyle changes and medication guidance, but some symptoms need prompt medical evaluation because they