Why can stretching or chemical irritation of visceral organs cause pain?

Visceral organs possess specialized pain receptors that respond to specific stimuli, such as overdistension (stretching) or chemical irritation, rather than the cutting or burning sensations that typically trigger pain in the skin. While many visceral organs can be cut without generating pain, they are highly sensitive to these specific mechanical and chemical changes.1

This physiological response is part of the body's mechanism for detecting damage, as tissues generally respond only to the specific stimuli they are likely to encounter. When these visceral receptors are activated, they transmit impulses to the spinal cord via afferent nerve fibers, which are then processed by the brain. Because visceral input often converges on the same spinal cord neurons as somatic tissues (such as the skin and muscles), the brain may misinterpret the origin of the signal, a phenomenon known as referred pain.12