OBJECTIVES Fibromyalgia (FM) is a chronic disorder characterized by multiple symptoms (e.g., pain, fatigue, cognitive dysfunction, sleep disturbance). The efficacy of most medications currently used to treat FM is limited, however, and problems of tolerability are often encountered, possibly causing many patients to discontinue therapy. This study examines patterns of use of prescription (Rx) medications with an eye toward assessing possible unmet clinical need. METHODS Using a large US health insurance database spanning the period 2005-2007, we identified all patients with ≥1 medical encounters for FM (defined as ICD-9-CM diagnosis code 729.1) in each of these three calendar years ("FM patients"). Rx medications possibly related to the treatment of FM ("FM-related") were defined to include antiepileptics, benzodiazepines, nonsteroidal anti-inflammatory drugs, muscle relaxants, sedatives/hypnotics, opioids, serotonin-norepinephrine reuptake inhibitors, selective serotonin reuptake inhibitors, L-dopa, and carbidopa. We examined receipt of FM-related Rx medications from two alternative perspectives: (1) period prevalence (receipt anytime during each calendar year); and (2) point prevalence (evidence of use on July 1 of each calendar year). Substantial differences between period prevalence and point prevalence rates may be suggestive of high rates of medication discontinuation. RESULTS A total of 51,885 patients met all study entry criteria. In each of the three years, approximately two-thirds of study subjects had evidence of receipt of FM-related Rx medications (65.2% in 2005, 66.5% in 2006, 66.7% in 2007). Corresponding point prevalence estimates, however, were substantially lower (July 1, 2005: 38.1%; July 1, 2006: 40.9%; July 1, 2007: 41.3%). CONCLUSIONS While roughly two-thirds of FM patients received FM-related Rx medications in any given year, point prevalence estimates were substantially lower, potentially suggestive of high rates of medication discontinuation. Further research is needed to better understand the extent to which these treatment patterns are indicative of unmet medical need with currently available Rx medications in patients with FM.