OBJECTIVE: Brand loyalty is an elusive, but sought after consumer attribute. Loyalty, however, is not clearly defined; especially for pharmaceuticals that have only recently been associated with their brands. METHODS: Brand loyalty was assessed from a national Health care survey, fielded June 2002 to 30,000 online U.S. adults. For this analysis, three conditions were chosen to represent a range of consumer types. Respondents (n = 7,209) were diagnosed and taking a prescription (Rx) for: depression (20% diagnosed, 51% Rx), gastroesophageal reflux disease (GERD, 10% diagnosed, 64% Rx), and/or high cholesterol (23% diagnosed, 53% Rx). Loyalty was evaluated by summing four Health care attitudes: would ask doctor for prescription; prescription advertising provides useful information; would ask doctor for specific medication; and insist that doctor give brand name medication. Responses were on a 5-point scale: 1 = strongly disagree and 5 = strongly agree. Final scores ranged from 4-20 (mean = 12, standard deviation = 2.8). Loyalty was then categorized as low (score 4-9) 18%, moderate (10-14) 65%, and high (15-20) 16%. RESULTS: Loyal consumers were younger, with more severe disease and comorbid illnesses. They sought information frequently and from more sources. Notably, loyal consumers requested medications more than three times more than those with low loyalty. Between 9-19% requested one of their high cholesterol, depression, or GERD medications. Requesters were more likely to be men. They had positive, proactive Health care attitudes and sought information from a variety of sources. Notably, consumers who requested medications remained on them up to six months longer. CONCLUSIONS: There is a small, but distinct group of pharmaceutical brand loyalists that is proactive and more likely to request prescription medications. Those who request medications trust doctors' advice and stay on therapy longer. These are our target patients. They can be reached through doctors, the internet, and family and friends with the information they need to make sound Health care decisions.