Indigestion, medically called dyspepsia, is the physical sensation of your digestive system struggling to process food effectively. It is essentially a "stomach upset" that occurs in the upper abdomen.

Here is a description of what happens and what it feels like:

1. The Physical Sensation (What it feels like)

Indigestion is rarely a sharp pain. Instead, it is described as a gnawing discomfort or a vague burning sensation located right in the center of your upper belly (between the bottom of your breastbone and your belly button).

The "Brick" Feeling: Many people describe it as feeling like they swallowed a brick. You feel uncomfortably full, tight, and heavy, even if you haven't eaten a large meal.

The Bloat: Your stomach may feel distended or swollen, often leading to the need to belch or burp to relieve pressure.

The Heat: There is often a sense of heat or "sourness" in the stomach, which can sometimes rise up toward the chest (heartburn).

2. The Mechanism (What is happening inside)

Under normal conditions, your stomach produces strong acid to break down food, and a protective mucous layer shields the stomach lining from being burned by that acid.

During indigestion, this balance is disrupted:

Acid Irritation: The protective lining may be weakened, or there may be an excess of acid, allowing the digestive juices to irritate the sensitive lining of the stomach (mucosa). This causes the burning and gnawing feeling.

Poor Motility: The muscles in the stomach may not be contracting properly. Instead of squeezing food down into the small intestine efficiently, the stomach remains relaxed and full for too long (delayed gastric emptying). This causes that heavy, "stuffed" feeling and bloating.

3. The Context

Indigestion is almost always event-based. It typically arises during or shortly after eating. It is the body's signal that the current load of food—whether due to volume, spiciness, fat content, or speed of eating—is overwhelming the stomach's current ability to digest it comfortably.