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Published on: March 22, 2014
Sex hormone suppression by intrathecal opioids: a prospective study
Lindy J Roberts1, Phillip M Finch, Peter T Pullan
1Western Australian Pain Management Centre, Department of Anesthesia, Sir Charles Gairdner Hospital, Western Australia, Australia. lindyr@cyllene.uwa.edu.au
Intrathecal opioids significantly lower testosterone levels in males with chronic pain, causing hypogonadism. Patients require monitoring and potential testosterone replacement therapy for sexual function and bone health.
Area of Science:
- Endocrinology
- Pain Management
- Pharmacology
Background:
- Chronic noncancer pain affects many individuals.
- Intrathecal opioids are used for pain management.
- Previous observations suggest sexual dysfunction in males on intrathecal opioids.
Purpose of the Study:
- To investigate the hypothesis that intrathecal opioids suppress the hypothalamic-pituitary-gonadal axis.
- To assess the impact of intrathecal opioids on testosterone levels and sexual function.
Main Methods:
- Prospective, nonrandomized study.
- Evaluated 10 males with chronic noncancer pain.
- Assessed hypogonadism via clinical and biochemical markers at baseline and during 12 weeks of intrathecal opioid therapy.
Main Results:
- Significant reduction in serum testosterone (p <0.0001) from 7.7 nmol/L to 2.0-4.0 nmol/L at 1, 4, and 12 weeks.
- Associated decrease in libido and potency.
- Luteinizing hormone and follicle-stimulating hormone levels remained normal, indicating central suppression.
Conclusions:
- Intrathecal opioid administration can lead to hypogonadotrophic hypogonadism.
- Informed consent should include discussion of this effect and its management.
- Monitoring of the hypothalamic-pituitary-gonadal axis and testosterone replacement are recommended for long-term therapy to improve sexual function and prevent hypogonadism-related metabolic effects like osteoporosis.
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