Definition and Cause
GERD (Gastroesophageal Reflux Disease) is a chronic condition where stomach acid frequently flows back into the esophagus, causing irritation. Common causes include a weak or relaxed lower esophageal sphincter, obesity, and certain dietary habits.

Symptoms
Typical symptoms include heartburn, regurgitation of food or sour liquid, difficulty swallowing, and chest pain, especially after eating.

Diagnosis
GERD is diagnosed using methods like endoscopy, esophageal pH monitoring, and manometry to assess esophageal function and acid levels.

Treatment Options
a. Lifestyle changes: Avoid large meals, don't lie down after eating, lose weight, and elevate the head of the bed.
b. Medications: Antacids, H2-receptor blockers, proton pump inhibitors, and prokinetics.

When to See a Doctor
Seek medical advice if experiencing severe chest pain, difficulty swallowing, or if symptoms persist despite treatment.