Tetany

Tetany is involuntary muscle stiffness or cramping, often in the hands, feet or around the mouth, caused by over-excitable nerves. In breathwork it usually follows fast breathing: lower CO₂ raises blood pH, less calcium stays freely available, and the hands may curl into a claw-like position that eases within minutes.

It is common in conscious connected breathing and usually not dangerous, though it can feel unsettling. Softening the breath, slowing the exhale and relaxing the hands typically lets it ease. Facilitators often explain it in advance so that participants are not alarmed if it appears. Persistent or severe symptoms, or tetany outside of breathwork, need medical assessment.