How does Cymbalta treat fibromyalgia?

Cymbalta may be used to treat symptoms of fibromyalgia. Fibromyalgia is a long-lasting disorder that may cause pain, stiff and tender muscles, fatigue and problems with falling asleep or staying asleep. Scientists are not exactly certain how Cymbalta helps makes patients with fibromyalgia feel better; fibromyalgia itself is poorly understood. Many believe the pain is due to changes in the nervous system which cause nerve cells to fire off too many signals. Researchers think that Cymbalta helps calm down these pain signals by increasing the level of two naturally occurring substances called serotonin and norepinephrine. Cymbalta blocks serotonin and norepinephrine from re-entering cells, and therefore raises the levels of the substances in the rest of the body. This process is thought to improve mood and relieve pain in patients with fibromyalgia.
                                                                                                     

I will let the pharmacist answer this question as to the pharmalogical effects.

However, as a patient advocate, I must bring up and important interaction between Cymbalta and triptans, such as Imitrex used to treat migraine headaches. There is a potential risk for serotonin syndrome, which can be a life threatening. Please see what the National Institute of Health has to say about it at http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0004531/

Severe headaches are a co-morbid condition with FM, so if you have frequent migraines and use triptans to treat them, please discuss this with your doctor or pharmacist.