Abstract
Generic (i.e. non-branded medicine) and therapeutic (i.e. a less expensive drug from the same class) substitution of medication provides considerable financial savings, but may negatively impact on patients. We report secondary qualitative/quantitative analysis of stroke survivors from a pilot randomised controlled brief intervention to increase adherence to medication. Patients’ experiences of medication changes were examined in conjunction with electronically-recorded medication adherence. Twenty-eight patients reported frequent medication changes (e.g. size/shape/colour/packaging) and two-thirds of these reported negative effects, resulting in, at least, confusion and, at worst, mistakes in medication-taking. Patients reporting a direct effect on their medication-taking (n = 6) demonstrated poorer objectively-measured adherence (i.e. % doses taken on schedule) than those reporting confusion [mean difference = 19.9, 95 % CI (2.0, 37.8)] or no problems [mean difference = 20.6, 95 % CI (1.6, 40.0)]. Changes to medication resulting from switching between generic brands can be associated with notable problems, including poorer medication adherence, for a significant minority.
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Notes
A third patient reported spending the night in the hospital after accidentally over-dosing due to confusing different tablet strengths after his GP changed his warfarin dosage (but not a brand switch):“When I was on… I think I had five 1[mg]s. I only had 5 and 1 s, and the dosage went down I think from 5[mg] to 4. And I took four 5 mg pills instead of four singles. So I overdosed 5 times… I spent a night in the infirmary.” (Male, aged 67).
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Acknowledgments
This project was funded by a grant from the Scottish Government, Department of Health, Chief Scientist Office; reference number CZH/4/569. We would like to thank the doctors and nurses at the Western General Hospital stroke clinic and ward for their help in recruitment, and the patients for giving up their time to take part.
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Chambers, J.A., O’Carroll, R.E., Dennis, M. et al. “My doctor has changed my pills without telling me”: impact of generic medication switches in stroke survivors. J Behav Med 37, 890–901 (2014). https://doi.org/10.1007/s10865-013-9550-5
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DOI: https://doi.org/10.1007/s10865-013-9550-5