SummaryWe investigated reasons for non-treatment of osteoporosis and discontinuation of osteoporosis therapy. Barriers to treatment include patients’ preference for alternative treatments and a fear of possible side effects. Side effects are a common reason for treatment discontinuation, and they may be associated with a lack of willingness to restart treatment.Purpose/introductionOsteoporosis patients commonly cite treatment-related side effects, or the fear thereof, as a reason for discontinuing or not initiating anti-osteoporosis medications. The purpose of this study was to investigate, from the patient’s perspective, reasons for (i) non-treatment of osteoporosis and (ii) discontinuation of osteoporosis therapy.MethodsThis was an internet-based survey of postmenopausal women in the USA who self-reported having been diagnosed with osteoporosis. Respondents were recruited from consumer research panels and received nominal compensation.ResultsWithin the surveyed population (N = 1407), 581 patients were currently being treated, 503 had never been treated, and 323 had previously been treated. Among patients never treated for osteoporosis, the highest ranking reasons for non-treatment were the use of alternative treatments such as over-the-counter vitamins/supplements (57.5 % of respondents) and fear of side effects (43.9 %). Among previously treated patients, frequent reasons for discontinuation included the direction of the physician (41.2 % of respondents), concerns about long-term safety (30.3 %), and the experience of side effects (29.8 %). When asked about their willingness to restart their osteoporosis medication, previously treated patients who were not willing (N = 104) to restart had a higher frequency of experiencing side effects (44.2 versus 20.5 % of those willing; P < 0.001).ConclusionsFrom the osteoporosis patient’s perspective, barriers to prescription treatment include a preference for alternative, non-prescription treatments and a fear of possible side effects. Side effects are one of the most common reasons for discontinuing osteoporosis medications, and they appear to be associated with a lack of willingness to restart treatment.Electronic supplementary materialThe online version of this article (doi:10.1007/s11657-016-0272-5) contains supplementary material, which is available to authorized users.