Hypersensitivity to pain

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In medicine, hypersensitivity to pain (also known as hyperalgesia ) is an excessive sensitivity to pain and a reaction to a usually painful stimulus, but also a painful reaction to normally non-painful stimuli. The cause is the sensitization of the nociceptors by certain endogenous substances that z. B. be released from tissue in the event of inflammation, against mechanical and thermal stimuli. As a result, the stimulus threshold (pain threshold) drops and common pain stimuli such as strong pressure, heat and cold trigger stronger pain signals than usual. The lowered pain threshold also means that weak, otherwise non-painful effects in the area of ​​inflammation trigger pain. Hyperalgesia is a form of hyperesthesia , the generic term for excessive sensitivity to a stimulus.

Indications for hyperalgesia result from the anamnesis . In the neurological examination, to diagnose hyperalgesia, the affected skin area is touched with the pointed end of a broken wooden stick, for example. In the presence of hyperalgesia, the patient then complains of excessive pain. In the case of inflammation-related hyperalgesia, even the light touch is perceived as painful, e.g. B. over an abscess.

A variety of neurological diseases can underlie the symptom of hyperalgesia.

Distinguished from hyperalgesia is the allodynia . This describes a sensation of pain that arises in response to non-painful stimuli. Stroking with a feather can be perceived as painful.

Hypalgesia or hypoalgesia, on the other hand, refers to a reduced sensation of pain in response to a stimulus that is usually painful. Pain insensitivity is brought about by pain therapy or is a pathological lack of pain .

literature

  • A. Latremoliere, CJ Woolf: Central sensitization: a generator of pain hypersensitivity by central neural plasticity. In: The journal of pain: official journal of the American Pain Society. Volume 10, number 9, September 2009, pp. 895-926, doi : 10.1016 / j.jpain.2009.06.012 , PMID 19712899 , PMC 2750819 (free full text) (review).
  • M. Mumenthaler, H. Schliack, M. Stöhr: Lesions of peripheral nerves and radicular syndromes. 7th edition. Georg Thieme Verlag, Stuttgart 1998, ISBN 3-13-380207-0 .
  • D. Bridges, SW Thompson, AS Rice: Mechanisms of neuropathic pain. In: Br J Anaesth. 2001 Jul; 87 (1), pp. 12-26. PMID 11460801 (Full text freely available.)