Opioid medications do their job well, and they do so by turning on something called our opioid receptors, which are found in the brain as well as in the gastrointestinal tract and spinal cord. The opioid receptors help signal and communicate about pain in the body, and both the opiate-like substances our body makes itself (endogenously-produced opioids) and the pills we take (exogenously-administered opiates) activate these receptors.
However, what happens when the body's opioid receptors deal with long-term exposure to opioid agonists? Hormone levels begin to fall out of balance, with decreased levels of sex hormones including testosterone and estrogen, cortisol and dehydroepiandrosterone sulfate (DHEAS) circulating throughout the body. This is what recent research calls opioid-induced endocrinopathy.
Emerging research is finding that opioid usage begins to take a toll on the hypothalamic-pituitary-gonadal (HPG) axis, causing it to malfunction. What happens is that opioids bind themselves to opioid receptors in the body, and those that bind themselves in the brain (the hypothalamus) disrupt how the body produces and manages sex hormones (and the verdict is still out how the other two receptors play a role in this). The way things are supposed to work goes like this: The hypothalamus produces gonadotropin-releasing hormone (GnRH), which triggers the pituitary gland to produce a luteinizing hormone (LH) and follicle-stimulating hormone (FSH). LH and FSH trigger the reproductive organs to produce estrogen (in women) and testosterone (in men) -- this is the HPG axis at work. If the HPG axis isn't functioning properly, the results can mean big changes inside the body, including changes that may lead to opioid-induced hypogonadism, sluggish libido, irregular menstruation in women, erectile dysfunction in men, and both female and male infertility, among other problems [sources: Ballantyne, Sigman].
While the affects of opioids on fertility are not yet fully understood, current research suggests long-term opioid usage, including the use of prescription drugs such as Tramadol, may play a role in both male and female fertility.
More Great Links
- American Pain Society
- The American Academy of Pain Medicine
- Centers for Disease Control and Prevention: Planning for Pregnancy
- U.S. Food and Drug Administration: Index to Drug-Specific Information
- U.S. Department of Health and Human Services Office on Women's Health: Pregnancy and medicines fact sheet
- Agirregoitia, Ekaitz; Valdivia, Asier; Carracedo, Arkait; Casis, Luis; Gil, Javier; Subiran, Nerea; Ochoa, Carmen; and John Irazusta. "Expression and Localization of δ-, κ-, and μ-Opioid Receptors in Human Spermatozoa and Implications for Sperm Motility." The Journal of Clinical Endocrinology & Metabolism. Vol. 91, no. 12. Pages 4969-4975. 2006. (July 13, 2012) http://jcem.endojournals.org/content/91/12/4969.full
- Ballantyne, Jane C. "Opioid Analgesia: Perspectives on Right Use and Utility." Pain Physician. Vol. 10. Pages 479-491. 2007. (July 13, 2012) http://www.painphysicianjournal.com/2007/may/2007;10;479-481.pdf
- Benyamin, R.; Trescot, A.M.; Dalta, S.; Buenaventura, R.; Adlaka, R.; Sehgal, N.; Glaser, S.E.; and R. Vallejo. "Opioid complications and side effects." Pain Physician. Vol. 11, supp. 2. Pages S105-120. 2008. (July 13, 2012) http://www.ncbi.nlm.nih.gov/pubmed/18443635
- Christo, Paul J. "Opioid effectiveness and side effects in chronic pain." Anesthesiology Clinics of North America. Vol. 21. Pages 699-713. 2003. (July 13, 2012) http://www.ctpainandwellness.com/ARTICLES/opiod%20effectiveness,%20NAC.pdf
- Colameco, Stephen; and Joshua S. Coren. "Opioid-Induced Endocrinopathy." The Journal of the American Osteopathic Association. Vol. 109, no. 1. Pages 20-25. 2009. (July 13, 2012) http://www.jaoa.org/content/109/1/20.long
- Crosta, Peter. "All About Opioids and Opioid-Induced Constipation." Medical News Today. (July 13, 2012) http://www.medicalnewstoday.com/info/oic/
- Finch, Philip M.; Roberts, Lindy J.; Price, Leanne S.; Hadlow, Narelle C.; and Peter T. Pullman. "Hypogonadism in Patients Treated with Intrathecal Morphine." Clinical Journal of Pain. Vol. 16, no. 3. Pages 251-254. 2000. (July 13, 2012) http://journals.lww.com/clinicalpain/Abstract/2000/09000/Hypogonadism_in_Patients_Treated_With_Intrathecal.11.aspx
- Fiore, Kristina. "Opioids in Early Pregnancy May Be Tied to Birth Defects." MedPage Today. 2011. (July 13, 2012) http://www.medpagetoday.com/OBGYN/Pregnancy/25167
- Katz, Nathaniel. "The Impact of Opioids on the Endocrine System." Pain Management. Vol. 1, no. 9. 2005. (July 13, 2012) http://www.inflexxion.com/uploadedFiles/Publications/Publications/Katz_2005_painmgt.pdf
- March of Dimes. "Alcohol and drugs." 2008. (July 13, 2012) http://www.marchofdimes.com/pregnancy/alcohol_prescription.html
- Ogbru, Omudhome. "tramadol, Ultram, Ultram ER." MedicineNet.com. http://www.medicinenet.com/tramadol/article.htm
- Sigman, Mark. "Medications that impair male fertility." The Journal of Family Practice. Vol. 5, no. 2. 2007. (July 13, 2012) http://www.jfponline.com/Pages.asp?AID=7104
- The National Alliance for Advocates for Buprenorphine Treament. "What is the difference between "opioids" and "opiates"?" (July 13, 2012) http://www.naabt.org/faq_answers.cfm?ID=3
- U.S. National Library of Medicine. "Tramadol." 2011. (July 13, 2012) http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0000960/
- Waldhoer, M.; Bartlett, S.E.; and J.L. Whistler. "Opioid receptors." Annual Review of Biochemistry. Vol. 73. Pages 953-990. 2004. (July 13, 2012) http://www.ncbi.nlm.nih.gov/pubmed/15189164
- WebMD. "Chronic Pain Management." 2012. (July 13, 2012) http://www.webmd.com/pain-management/guide/understanding-pain-management-chronic-pain