Researchers have recently tested testosterone as an alternative treatment to alleviate symptoms in fibromyalgia patients, and report that an early study shows it to be effective in managing chronic pain with potentially fewer side effects than in existing treatments. The study entitled, “Treatment of pain in fibromyalgia patients with testosterone gel: Pharmacokinetics and clinical response,” was published in the journal International Immunopharmacology.
Current treatments for fibromyalgia (FM) including non-steroidal anti-inflammatory drug analgesics (NSAIDS), morphine-related opioid analgesics, and antidepressants, may cause gastrointestinal tract irritation, hyperplasia and sexual dysfunction. The mean age of FM onset in women, 44-53 years, overlaps with the mean age for menopause, 51 years, and several evidences have linked testosterone levels to pain, leading researchers to test whether testosterone therapy in these women could reduce pain without the side effects of common treatments.
The team conducted a Phase I/II pilot trial in 12 patients to verify whether testosterone delivered daily in the form of a transdermal gel could significantly increase serum testosterone levels, and treat the chronic pain and fatigue symptoms of FM. They select women aged between 40–55 years who had been diagnosed with FM using the American College of Rheumatology (ACR) criteria. Study participants were not receiving hormone therapy and kept taking their medication, except for analgesics, which could be reduced. During 28 days, researchers followed the increasing levels of testosterone, known as a pharmacokinetic study, in patients’ serum, observing that testosterone levels raised from 1.21 ng/mL on day 1 to 1.92 ng/mL on day 28. Pain parameters and other typical symptoms of FM were also assessed via patient questionnaires, and participants confirmed a significant decrease in muscle pain, stiffness, and fatigue, and increased libido during the study period.
“These findings are consistent with our hypothesis that restoration of premenopausal serum testosterone concentrations was expected to relieve symptoms that most specifically relate to testosterone deficiency, for example loss of muscle function, increased fatigue and loss of sexual desire,” the authors wrote in their report.
The transdermal gel formulation developed for this study was shown to keep testosterone levels stable, without spiking.
This offers a potentially alternative and safe replacement testosterone therapy to treat FM in patients whose blood testosterone levels are in the lower half of the reference range, such as in premenopausal and menopausal women. The researchers recommended further studies of testosterone replacement therapy in a formal double blind, placebo-controlled clinical trial.