<s>[INST] My 18 year old son is having pain under the sternum and it gets worse when he eats or even drinks water He woke up in the middle of the night when it first started and this is day 5. Went to Urgent care Friday night, says if is costochondritis but does not improve with ibuprofen. Has tries softer foods but still has pain when eating. [/INST] Thanks for your question on Chat Doctor. Since he is not improving with painkillers, I think he is having HERD (Castro Esophageal Reflux Disease) associated pain. It is due to laxity of gastroesophageal sphincter. Because of this the acid of the stomach tends to come up in the esophagus and cause the symptoms. So central chest pain under sternum can be due to HERD only. Ask him to follow these steps. 1. Avoid hot and spicy food. 2. Avoid large meals, instead take frequent small meals. 3. Avoid stress and anxiety. 4. Start proton pump inhibitor. 5. Go for walk after meals. 6. Keep 2 - 3 pillows under head in the bed. </s>