α₂‐Agonists as analgesic agents

Abstract

It is well known that norepinephrine is involved in the control of pain by modulating pain-related responses through various pathways. alpha(2)-Adrenergic agonists have a well-established analgesic profile and, in the recent years, have found a wider application, in particular as adjunct to anesthetics and analgesics in perioperative settings. This review analyzes the alpha(2)-agonists currently in clinical use, starting from the prototype Clonidine, as well as the most promising and studied molecules. In addition, an overview of the imidazoles, imidazolines, and hydroxyethyl-thioureas derivatives published in both the open and patented literature is presented, providing chemical description and pharmacological data. Finally, the most commonly alpha(2)-agonists used in veterinary medicine are described.

Clonidina subaracnoidea y respuesta al trauma en cirugías cardíacas con circulación extracorpórea

“…El uso de la clonidina sobre el neuroeje en humanos empezó en 1984 16 . Desde entonces, muchas investigaciones sugieren que la clonidina espinal potencia los efectos de los opiáceos y de los anestésicos locales 7,13 . Por tanto, cuando se da esa asociación, puede ser difícil separar los efectos producidos solamente por la clonidina.…”

“…Además de eso, la clonidina ha revelado una capacidad moduladora de la respuesta al estrés quirúrgico y la aplicación significativa en el tratamiento del dolor crónico [10][11][12][13] . Algunos estudios también sugieren que la clonidina actúa en la reducción de la morbimortalidad perioperatoria de pacientes de riesgo para coronariopatía 14,15 .…”

NMDA Receptor Antagonists, Gabapentinoids, α-2 Agonists, and Dexamethasone and Other Non-Opioid Adjuvants

“…49 Dexmedetomidine is a more selective α-2 agonist and has a short terminal half-life of 2 hours. 50 It produces antinociception by inhibiting activation of microglia cells and signal-regulated kinase in the spinal dorsal horn after nerve injury 51,52 and reduces perioperative catecholamine release.…”

Basic/Translational Development of Forthcoming Opioid- and Nonopioid-Targeted Pain Therapeutics

“…180–182 Alpha 2 agonists delivered systemically or intrathecally have significant effects upon acute, inflammatory and nerve injury hyperpathias. 183,184 In humans neuraxial alpha2 agonist (clonidine) and systemic (clonidine, tizanidine dexmedetomidine) have analgesic properties with sedation being a common sequelae of the actions of these agents. Dexmedetomidine is not a controlled substance.…”