Frösteln

Frösteln is the involuntary shivering or tremor that people experience in response to cold exposure, fever, or illness. It is a physiological mechanism in which rapid, rhythmic skeletal muscle contractions generate heat to raise the body's core temperature. Shivering is regulated by the hypothalamus, the brain’s temperature control center, and is often accompanied by peripheral vasoconstriction and sometimes goosebumps (piloerection).

Common causes include exposure to cold environments, acute infection or fever (often described as rigors, the intense chills that accompany fever), dehydration, malnutrition, or certain medications. Less frequently, tremor disorders or neurological conditions can produce similar shaking but with different patterns or triggers.

Clinical features typically include a sensation of cold, observable trembling, and cool or pale skin. If shivering is persistent or accompanied by confusion, chest pain, shortness of breath, severe dehydration, or a high fever, medical evaluation is advised. Frösteln may be a sign of hypothermia in extreme cold or a fever in infection, so assessing body temperature is important.

Diagnosis is usually clinical, based on history and examination, with measurement of core temperature. Treatment focuses on warming and addressing the underlying cause. For mild cases, blankets, warm clothing, and warm fluids help. Treat fever with appropriate antipyretics and manage infections or dehydration as indicated. In hypothermia or severe rigors, medical care may be required.

Prognosis is generally favorable in healthy individuals, but persistent or recurrent frösteln with other symptoms warrants medical assessment to rule out serious underlying conditions.