Duloxetine appears effective in treating fibromyalgia.VANCOUVER, B.C. -- Duloxetine is a safe and effective treatment for fibromyalgia symptoms in both depressed and nondepressed women, Lesley Arnold, M.D., reported at the annual meeting of the American Psychosomatic Society.
Duloxetine (Cymbalta) is approved for the treatment of both major depression and diabetic neuropathic pain. The drug's efficacy in treating both pain and depression--which often co-occur in fibromyalgia--is probably due to its dual action as a selective serotonin and norepinephrine reuptake inhibitor Norepinephrine reuptake inhibitors (NRIs), also known as noradrenaline reuptake inhibitors (NARIs), are compounds that elevate the extracellular level of the neurotransmitter norepinephrine in the central nervous system by inhibiting its reuptake from the , said Dr. Arnold, a psychiatrist who is director of women's health research at the University of Cincinnati The University of Cincinnati is a coeducational public research university in Cincinnati, Ohio. Ranked as one of America’s top 25 public research universities and in the top 50 of all American research universities, .
In one of two 12-week studies funded by Lilly Research Laboratories Lilly Research Laboratories is the organizational name of the global pharmaceutical research and development organization of Eli Lilly and Company, one of the world's largest pharmaceutical corporations. , a total of 354 adult women who met the American College of Rheumatology's criteria for primary fibromyalgia were randomized to receive 60 mg of duloxetine once a day (118), 60 mg twice daily (116), or placebo (120).
Significant differences in the Brief Pain Inventory Brief Pain Inventory Neurology A brief, relatively simple, self-administered questionnaire for evaluating pain, which addresses the relevant aspects of pain–history, intensity, timing, location, and quality and the pain's ability to interfere with the Pt's (BPI) average 24-hour pain score and the Fibromyalgia Impact Questionnaire (FIQ) were seen within 1 week in both the 60 mg/day and 120 mg/day duloxetine groups compared with placebo, with no significant difference between the two dosages.
In the low- and high-dose groups, 41% of patients experienced a 50% reduction in overall pain, compared with 23% of patients on placebo.
Significant improvements over placebo were also seen in the FIQ total, pain, fatigue, and restfulness upon awakening scores; in the mean tender point threshold and number of tender points; in the Clinical Global Impression (CGI) and Patient Global Impression of Improvement (PGI) scores; in other BPI subscale measures of pain severity and interference; and in several quality of life and functional measures.
This study replicated several findings from a previously-published trial of 207 fibromyalgia patients that included a small number of men. Dr. Arnold presented the findings of both trials together in a poster at the meeting.
In the earlier study, 104 patients (89% women) were randomized to 120 mg/day of duloxetine, and 103 (89% women) to placebo. Duloxetine patients improved significantly more than did placebo-treated patients on the FIQ total score, but not significantly more on the FIQ pain score (Arthritis Rheum. 2004;50:2974-84).
Duloxetine-treated patients also had significant reductions compared with placebo-treated patients in BPI scores for average pain severity and interference from pain, number of tender points, and FIQ stiffness, as well as several other fibromyalgia-specific and quality of life measures. The differences were only significant for women, but the number of men was quite small.
Major depression was present in approximately 40% of the subjects in the earlier single-dose study and in about one-fourth of the subjects in the two-dose study. In both studies, there were no differences between depressed and nondepressed patients in duloxetine efficacy in alleviating pain and fibromyalgia symptoms, suggesting that these effects are not simply due to an improvement in mood, she noted.
In the first study, duloxetine was significantly more likely than placebo to be associated with side effects including constipation, dry mouth, insomnia, and a small mean increase in heart rate. These were typically mild to moderate in severity. Also in that study, anxiety was reported significantly less often with duloxetine than with placebo.
In the more recent study, nausea, dry mouth, constipation, diarrhea, somnolence somnolence /som·no·lence/ (som´no-lens) drowsiness or sleepiness, particularly in excess.
1. A state of drowsiness; sleepiness.
2. , decreased appetite and weight, and a small mean increase in systolic Systolic
The phase of blood circulation in which the heart's pumping chambers (ventricles) are actively pumping blood. The ventricles are squeezing (contracting) forcefully, and the pressure against the walls of the arteries is at its highest. and diastolic blood pressure Diastolic blood pressure
Blood pressure when the heart is resting between beats.
Mentioned in: Hypertension were among the side effects reported more frequently by duloxetine-treated patients than by those on placebo. These side effects were also generally mild to moderate in severity. In all, the drug was safely administered and well tolerated.