Opioid analgesics activate nociceptive system

To date, it is proved that opioid analgesics activate not only the antinociceptive system, but also cause proof activate nociceptive system

    Last seen central sensitization, which is the basis for the activation of excitatory amino acids (glutamate and aspartate) at the level of NMDA-receptors. Impact on the μ-opioid receptors initiates the activation of NMDA-receptors by removing the blocking Mg2 + ions from their receptor channels. This process contributes to the activation of protein kinase C activation Pronotsitseptivnaya exceed in intensity the activity of nociceptive inhibitory systems. Thus, opioid analgesics alone are able to induce delayed hyperalgesia until the development of allodynia (pain perception nebolevyh incentives). We can say that they have on nociception two opposite effects: at the initial stage is dominated by analgesia, which was later replaced by hyperalgesia.
   In conclusion, we present some of the tenets of evidence based medicine, on postoperative use of opioid analgesics (Acute Pain Management: Scientific Evidence, 3-rd edition, 2010):
1. Opioids in high doses can induce hyperalgesia (Grade I)
2. In the treatment of acute pain one opioid has no advantage over the other, although some opioids may have certain advantages in those or other patients (Grade II)
3. The frequency of significant side effects of opioids is a dose-dependent nature of the (Grade II)
4. Age of the patient to a greater extent than its weight, determines the need for opioid analgesics, although there is individual variability (level of evidence IV)