Analgesics

• There are three types of analgesics

  Narcotic analgesics (Opioid analgesics)

  Non-narcotic analgesics (Non-steroidal anti-inflammatory drugs)

  Adjuvant analgesics or Co-analgesics
• mu receptor

  • sedation; euphoria; inhibition of respiration;
• Delta receptor

  • modulation of hormone and neurotransmitter release
• Kappa receptor

  • dysphoria; psychotomimetic effects; sedation;
  • slowed Gl transit
• Pure agonists (primarily at μ, perhaps at k & delta)

  • morphine, hydromorphine, oxymorphine
  • methadone
  • fentanyl, sufentanil, alfentanil, remifentanil
  • levorphanol, oxycodone
  • codeine, hydrocodone, tramadol (weak μ agonist)
• Partial agonist and mixed agonist antagonists

  • butorphanol
  • nalbuphine (k agonist, μ antagonist)
  • pentazocine (k agonist, weak μ antagonist or partial agonist),
  • buprenorphine (partial μ agonist)
• Antagonist (all receptors)

  naloxone, naltrexone, nalmefene
• Monoamine oxidase inhibitor + Opioid

  • Hyperpyrexic coma
  • Hypertension
• Sedative hypnotic + Opioid

  • Increase CNS depression
  • Increase respiratory depression
• Antipsychotic agents + Opioid

  • Sedation increase
  • CVS eff ( antimuscarinic and alpha blocking action )