Opioid analgesic: Difference between revisions

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===Constipation===
===Constipation===
[[Constipation]] may be reduced by [[methylnaltrexone]], a mu-[[opioid receptor]] antagonist. In a [[randomized controlled trial]], 48% of patients receiving [[methylnaltrexone]] had a bowel movement compared to 15% of patients received placebo ([[number needed to treat]] = 3.0. [http://medinformatics.uthscsa.edu/calculator/calc.shtml?calc_rx_rates.shtml?eer=48.0&cer=15.0 Click here] to adjust these results for patients at higher or lower risk.)<ref>Thomas J, Karver S, Cooney GA, Chamberlain BH, Watt CK, Slatkin NE, Stambler N, Kremer AB, Israel RJ. [http://content.nejm.org/cgi/content/full/358/22/2332 Methylnaltrexone for opioid-induced constipation in advanced illness]. N Engl J Med. 2008 May 29;358(22):2332-43. PMID 18509120</ref> Although mu-receptors provide analgesia, [[methylnaltrexone]] is a charged quaternary amine so that it does not well cross the [[blood-brain barrier]].
[[Constipation]] may be reduced by [[methylnaltrexone]], a mu-[[opioid receptor]] antagonist. In a [[randomized controlled trial]], 48% of patients receiving [[methylnaltrexone]] had a bowel movement compared to 15% of patients received placebo ([[number needed to treat]] = 3.0. [http://medinformatics.uthscsa.edu/calculator/calc.shtml?calc_rx_rates.shtml?eer=48.0&cer=15.0 Click here] to adjust these results for patients at higher or lower risk.)<ref>Thomas J, Karver S, Cooney GA, Chamberlain BH, Watt CK, Slatkin NE, Stambler N, Kremer AB, Israel RJ. [http://content.nejm.org/cgi/content/full/358/22/2332 Methylnaltrexone for opioid-induced constipation in advanced illness]. N Engl J Med. 2008 May 29;358(22):2332-43. PMID 18509120</ref> Although mu-receptors provide analgesia, [[methylnaltrexone]] is a charged quaternary amine so that it does not well cross the [[blood-brain barrier]].
===Tolerance===
[[N-methyl-d-aspartate receptor]] activation may lead to neuropathic pain and tolerance.<ref name="pmid16629581">{{cite journal| author=Prommer E| title=Rotating methadone to other opioids: a lesson in the mechanisms of opioid tolerance and opioid-induced pain. | journal=J Palliat Med | year= 2006 | volume= 9 | issue= 2 | pages= 488-93 | pmid=16629581
| url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&retmode=ref&cmd=prlinks&id=16629581 | doi=10.1089/jpm.2006.9.488 }} <!--Formatted by http://sumsearch.uthscsa.edu/cite/--></ref> [[Methadone]], which is a [[N-methyl-d-aspartate receptor]] antagonist, may reduce tolerance.


==References==
==References==
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Opioid analgesics, also called narcotics, are drugs usually used for treating pain. Opiod analgesics are defined as "all of the natural and semisynthetic alkaloid derivatives from opium, their pharmacologically similar synthetic surrogates, as well as all other compounds whose opioid-like actions are blocked by the nonselective opioid receptor antagonist naloxone.[1]

Pharmacology

There a several opioid receptors. All are are G-protein-coupled cell surface receptors.

  • Mu receptors are responsible for analgesia.
  • Delta
  • Kappa

Available opioid analgesics

Current opioid analgesics are:[2]

  1. 18,19-dihydroetorphine
  2. Alfentanil
  3. Alphaprodine
  4. beta-casomorphins
  5. Buprenorphine
  6. Butorphanol
  7. carfentanil
  8. Codeine
  9. deltorphin I, Ala(2)-
  10. dermorphin
  11. Dextromoramide
  12. Dextropropoxyphene
  13. dezocine
  14. dihydrocodeine
  15. Dihydromorphine
  16. Diphenoxylate
  17. dynorphin (1-13)
  18. endomorphin 1
  19. endomorphin 2
  20. Enkephalin, Ala(2)-MePhe(4)-Gly(5)-
  21. Enkephalin, D-Penicillamine (2,5)-
  22. enkephalin-Met, Ala(2)-
  23. eseroline
  24. Ethylketocyclazocine
  25. Ethylmorphine
  26. Etorphine
  27. Fentanyl
  28. Heroin
  29. Hydrocodone
  30. Hydromorphone
  31. ketobemidone
  32. Levorphanol
  33. lofentanil
  34. Meperidine
  35. Meptazinol
  36. Methadone
  37. Methadyl Acetate
  38. Morphine
  39. Nalbuphine
  40. nocistatin
  41. Opiate Alkaloids
  42. Opium
  43. Oxycodone
  44. Oxymorphone
  45. paracymethadol
  46. Pentazocine
  47. Phenazocine
  48. Phenoperidine
  49. Pirinitramide
  50. Promedol
  51. protopine
  52. remifentanil
  53. Sufentanil
  54. Tilidine
  55. tyrosyl-1,2,3,4-tetrahydro-3-isoquinolinecarbonyl-phenylalanyl-phenylalanine

Drugs that are both mu-opioid receptor agonists and norepinephrine reuptake inhibitors.

  1. Tapentadol
  2. Tramadol

Effectiveness

Narcotics are commonly prescribed for pain, and their usage may be increasing.[3] In emergency rooms, non-Hispanic white patients are more likely to receive narcotics than patients of other ethnicities.[3]

Narcotics are effective for both short (1-16 weeks)[4] and long-term (6-24 months) use[5].

Narcotics, with long-term use, 80% of patients may have drug toxicity, most commonly gastrointestinal. In addition, substrance abuse and "aberrant medication-taking behaviors" may occur.[6] Advice for using administering chronic narcotics[7] and for treating acute pain among patients on chronic methadone is available[8].

Adverse effects

Constipation

Constipation may be reduced by methylnaltrexone, a mu-opioid receptor antagonist. In a randomized controlled trial, 48% of patients receiving methylnaltrexone had a bowel movement compared to 15% of patients received placebo (number needed to treat = 3.0. Click here to adjust these results for patients at higher or lower risk.)[9] Although mu-receptors provide analgesia, methylnaltrexone is a charged quaternary amine so that it does not well cross the blood-brain barrier.

Tolerance

N-methyl-d-aspartate receptor activation may lead to neuropathic pain and tolerance.[10] Methadone, which is a N-methyl-d-aspartate receptor antagonist, may reduce tolerance.

References

  1. ↑ Katzung, Bertram G. (2006). Basic and clinical pharmacology. New York: McGraw-Hill Medical Publishing Division, 512. ISBN 0-07-145153-6. 
  2. ↑ Anonymous (2024), Opioid analgesics (English). Medical Subject Headings. U.S. National Library of Medicine.
  3. ↑ 3.0 3.1 Pletcher MJ, Kertesz SG, Kohn MA, Gonzales R (2008). "Trends in opioid prescribing by race/ethnicity for patients seeking care in US emergency departments". JAMA 299 (1): 70–8. DOI:10.1001/jama.2007.64. PMID 18167408. Research Blogging.
  4. ↑ Furlan AD, Sandoval JA, Mailis-Gagnon A, Tunks E (2006). "Opioids for chronic noncancer pain: a meta-analysis of effectiveness and side effects". CMAJ 174 (11): 1589–94. DOI:10.1503/cmaj.051528. PMID 16717269. Research Blogging.
  5. ↑ Kalso E, Edwards JE, Moore RA, McQuay HJ (2004). "Opioids in chronic non-cancer pain: systematic review of efficacy and safety". Pain 112 (3): 372–80. DOI:10.1016/j.pain.2004.09.019. PMID 15561393. Research Blogging.
  6. ↑ Martell BA, O'Connor PG, Kerns RD, et al (2007). "Systematic review: opioid treatment for chronic back pain: prevalence, efficacy, and association with addiction". Ann. Intern. Med. 146 (2): 116–27. PMID 17227935. [e]
  7. ↑ Clinical Guidelines for the Use of Chronic Opioid Therapy in Chronic Noncancer Pain Roger Chou, Gilbert J. Fanciullo, Perry G. Fine, Jeremy A. Adler, Jane C. Ballantyne, Pamela Davies, Marilee I. Donovan, David A. Fishbain, Kathy M. Foley, Jeffrey Fudin, Aaron M. Gilson, Alexander Kelter, Alexander Mauskop, Patrick G. O'Connor, Steven D. Passik, Gavril W. Pasternak, Russell K. Portenoy, Ben A. Rich, Richard G. Roberts, Knox H. Todd, Christine Miaskowski, American Pain Society–American Academy of Pain Medicine Opioids Guidelines Panel The Journal of Pain - February 2009 (Vol. 10, Issue 2, Pages 113-130.e22,( DOI:10.1016/j.jpain.2008.10.008)
  8. ↑ Alford DP, Compton P, Samet JH (2006). "Acute pain management for patients receiving maintenance methadone or buprenorphine therapy". Ann. Intern. Med. 144 (2): 127–34. PMID 16418412. [e]
  9. ↑ Thomas J, Karver S, Cooney GA, Chamberlain BH, Watt CK, Slatkin NE, Stambler N, Kremer AB, Israel RJ. Methylnaltrexone for opioid-induced constipation in advanced illness. N Engl J Med. 2008 May 29;358(22):2332-43. PMID 18509120
  10. ↑ Prommer E (2006). "Rotating methadone to other opioids: a lesson in the mechanisms of opioid tolerance and opioid-induced pain.". J Palliat Med 9 (2): 488-93. DOI:10.1089/jpm.2006.9.488. PMID 16629581. Research Blogging.
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