I was diagnosed with Fibromyalgia at age 18 while a freshman in college. After numerous tests failed to indicate any other causes, an MRI showed tendonitis and bursitis in my right shoulder. The same pain was throughout my body. It started after I went on a new heart medication. When I stopped taking the med, the pain went away. Then I took a new antihistamine shortly thereafter, and again, the pain came back. After stopping the antihistamine, the pain went away. The third time I reacted with a drug, the pain never left and has remained ever since.