Encyclopedia of Pain

2007 Edition

Alpha(α) 2-Adrenergic Agonists in Pain Treatment

  • Carsten Bantel
  • Mervyn Maze
  • Laura Stone
  • George Wilcox
Reference work entry
DOI: https://doi.org/10.1007/978-3-540-29805-2_165


Alpha(α) 2-Agonists; α2c-adrenoceptor agonists; α2-receptor agonists; α2-adrenergic agonists; Alpha(α) 2-Adrenergic Receptor Agonists; α-agonists


Alpha2-adrenergic agonists are drugs that mediate their analgesic (antinociceptive) effects by acting on α2-adrenoceptors (α2A, α2B, α2C) in the peripheral and central nervous system.


Indications and Patients

Alpha2-adrenoceptor (α2AR) agonists are used for treatment of acute (intra- and post-operative) as well as chronic (neuropathic) pain states. They are effective in patients of all age groups. α2AR agonists have also been safely used in pregnancy, labour and during caesarean sections. Furthermore, there is evidence that they provide haemodynamic stability in patients with co-existing cardiovascular diseases during phases of noxious stimulation (e.g. orotracheal intubation) by attenuating the sympathetic response.

Dose and Route of Administration (Table 1)

With  clonidine being the prototypical α2AR...

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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Carsten Bantel
    • 1
  • Mervyn Maze
    • 1
  • Laura Stone
    • 2
  • George Wilcox
    • 2
  1. 1.Magill Department of AnaestheticsChelsea and Westminster CampusImperial College of Scienceand Medicine, London, UK
  2. 2.Department of NeuroscienceUniversity of MinnesotaMinneapolisUSA