The prevalence of fibromyalgia in our clinical practices is about 2%-3%. But it may feel much higher, because some of these patients use a lot of staff and office time. Vacillations in our certainty about the diagnosis, inadequate time to differentiate new problems from the underlying one, failing to engage the patient in disease self-management, and inadequately exhausting the plethora of pharmacologic management options (however weak the data may be for each one) make care of patients with fibromyalgia challenging. Unfortunately, many of these patients are treated with chronic opioids.
So, maybe you have tried every pharmacologic option under the sun. But have you tried memantine?
Dr. Bárbara Olivan-Blázquez of the University of Zaragoza, Spain, and colleagues evaluated the efficacy of memantine for pain symptom control in fibromyalgia ( Pain. 2014 Dec;155:2517-25 ).
In this study, 63 patients with fibromyalgia were randomized to 20 mg/day of memantine or matching placebo for a total of 6 months, including an initial 1-month up-titration period. Follow-up occurred at 3 months and 6 months.
Compared with placebo, memantine decreased pain and depression at 3 months and 6 months. It also increased cognitive function and overall perceptions of function at 3 months and 6 months. More than 80% of patients completed the trial. Dizziness and headaches were the most commonly reported symptoms.
Why does it work? Memantine blocks glutamate, and glutamate may be a player in perpetuating the pain cycle for patients with fibromyalgia. Previously, memantine had been shown to be effective in other pain conditions such as complex regional pain syndrome and phantom limb pain. Memantine is well tolerated and is generically available. In my location, I was able to locate it for less than $1 per day of therapy.
So, before giving up hope or reaching for the opioid du jour, memantine may be worth a trial to decrease pain and improve function in our patients with fibromyalgia.
Dr. Ebbert is professor of medicine, a general internist at the Mayo Clinic in Rochester, Minn., and a diplomate of the American Board of Addiction Medicine. The opinions expressed are those of the author and do not necessarily represent the views and opinions of the Mayo Clinic. The opinions expressed in this article should not be used to diagnose or treat any medical condition nor should they be used as a substitute for medical advice from a qualified, board-certified practicing clinician. Dr. Ebbert has no relevant financial disclosures about this article. Follow him on Twitter @jonebbert .