Indigestion, also known as dyspepsia, is a common digestive problem characterized by discomfort or pain in the upper abdomen. It can manifest as a feeling of fullness, bloating, burning sensation, or even nausea and vomiting. Indigestion can be caused by various factors, including:

1. Overeating: Consuming large meals or eating too quickly can overwhelm the digestive system and lead to indigestion.
2. Fatty or Spicy Foods: High-fat or spicy meals can relax the lower esophageal sphincter, allowing stomach acid to flow back into the esophagus, causing heartburn and indigestion.
3. Stress and Anxiety: Emotional stress can lead to indigestion by affecting digestive processes and increasing stomach acid production.
4. Gastroesophageal Reflux Disease (GERD): Chronic acid reflux, where stomach acid regularly flows into the esophagus, can cause persistent indigestion and damage the esophagus lining.
5. Medications: Certain drugs, such as nonsteroidal anti-inflammatory drugs (NSAIDs) and antibiotics, can irritate the stomach lining and trigger indigestion.