We attempted a randomized, double blind trial of placebo vs cyclobenzaprine (Flexeril) in 40 female patients with fibromyalgia from a private rheumatology practice in Maine. Patient reports and physician global assessments indicated that cyclobenzaprine was more effective than placebo in alleviating symptoms of fibromyalgia in a subgroup of patients. However, most patients in the study had more accurate perceptions of drug effects than had been predicted and were able to identify the test drug. How much this awareness contributed to the perceived effectiveness of cyclobenzaprine is unknown.