The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) in 2014 stated that there was a lack of evidence for opioids for most people. The Association of the Scientific Medical Societies in Germany in 2012 made no recommendation either for or against the use of weak opioids because of the limited amount of scientific research addressing their use in the treatment of FM. They strongly advise against using strong opioids. The Canadian Pain Society in 2012 said that opioids, starting with a weak opioid like tramadol, can be tried but only for people with moderate to severe pain that is not well-controlled by non-opioid painkillers. They discourage the use of strong opioids and only recommend using them while they continue to provide improved pain and functioning. Healthcare providers should monitor people on opioids for ongoing effectiveness, side effects, and possible unwanted drug behaviors.A 2015 review found fair evidence to support tramadol use if other medications do not work. A 2018 review found little evidence to support the combination of paracetamol (acetaminophen) and tramadol over a single medication.
Fibromyalgia is associated with mental health issues like anxiety, posttraumatic stress disorder, bipolar disorder, and depression. Patients with fibromyalgia are five times more likely to have major depression than the general population.Fibromyalgia and numerous chronic pain conditions frequently coexist. These include chronic tension headaches, myofascial pain syndrome, and temporomandibular disorders. Multiple sclerosis, post-polio syndrome, neuropathic pain, and Parkinsons disease are four neurological disorders that have been linked to pain or fibromyalgia. Fibromyalgia largely overlaps with chronic fatigue syndrome and may share the same pathogenetic mechanisms.Comorbid fibromyalgia has been reported to occur in 20–30% of individuals with rheumatic diseases. It has been reported in people with noninflammatory musculoskeletal diseases.The prevalence of fibromyalgia in gastrointestinal disease has been described mostly for celiac disease and irritable bowel syndrome (IBS). Fibromyalgia has also been linked with obesity. Other conditions that are associated with fibromyalgia include an overactive bladder. Risk factors
The cause of fibromyalgia is unknown. However, several risk factors, genetic and environmental,  have been identified. Genetics
Genetics play a major role in fibromyalgia, and may explain up to 50% of the disease susceptibility. Fibromyalgia is potentially associated with polymorphisms of genes in the serotoninergic, dopaminergic and catecholaminergic systems. Several genes have been suggested as candidates for susceptibility to fibromyalgia. These include SLC64A4, TRPV2, MYT1L, NRXN3, and the 5-HT2A receptor 102T/C polymorphism.