Fibromyalgia (FM) is an idiopathic, chronic, nonlocalized pain syndrome accompanied by generalized tenderness. From 2% to 4% of people in the U.S. are affected. Although usually recognized as a disorder that predominates in middle-aged women, it can also affect men and adolescents. In addition to experiencing widespread pain and tenderness, patients may also report sleep difficulties, fatigue, anxiety, depression, paresthesias, stiffness, and an overall decline in physical function. These symptoms are distressing and may have a severe impact on quality of life.
Propecia from Mexico
The American College of Rheumatology uses specific criteria for diagnosing FM. The diagnosis is based on the presence of widespread pain for a period of at least three months and on the presence of 11 tender points among 18 specific anatomic sites.
The pathophysiology of FM is poorly understood. Emerging insights suggest that it is a disorder of central nervous system (CNS) pain-processing mechanisms, which results in increased nociceptive sensitivity. The augmented experience of pain is thought to be associated with either (1) excessive spinal facilitation of afferent nociceptive signaling to higher cortical pain-processing regions or (2) deficiencies in descending cortical mechanisms that dampen nociception.
Both ascending and descending nociceptive pathways are regulated through multiple neurotransmitters, including serotonin (5-HT) and norepinephrine. It is hypothesized that abnormal functioning of the noradrenergic and serotonergic neurons in the ascending and descending pathways lead to the painful symptoms of FM.
Treatment options include nonpharmacological and pharmacological therapies. The most common nonpharmacological treatments are exercise, patient education, and cognitive behavioral therapy, which have shown some efficacy in randomized, placebo-controlled trials.
Pharmacological therapies include a variety of antidepressants, antiepileptics, opioids, and non-steroidal anti-inflammatory agents (NSAIDs). Of the wide variety of medications available to treat FM, only three are approved by the FDA: pregabalin (Lyrica, Pfizer), duloxetine (Cymbalta, Eli Lilly), and milnacipran (Savella, Forest/Cypress Bioscience).
Milnacipran is a dual serotonin and norepinephrine reuptake inhibitor (SNRI) that is more selective for norepinephrine reuptake. It has been approved for the treatment of depression in parts of Europe and Asia since the late 1990s and has now been approved for patients with FM.5 This article reviews the pharmacology, pharmacokinetics, safety, and efficacy of milnacipran for FM.
Mexican pharmacy savella: