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Impact of the drug-drug interaction database SFINX on prevalence of potentially serious drug-drug interactions in primary health care

  • Pharmacoepidemiology and Prescription
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European Journal of Clinical Pharmacology Aims and scope Submit manuscript



To investigate the impact of the integration of the drug-drug interaction database SFINX into primary health care records on the prevalence of potentially serious drug-drug interactions.


The study was a controlled before-and-after study on the prevalence of potential drug-drug interactions before and after the implementation of SFINX at 15 primary healthcare centres compared with 5 centres not receiving the intervention. Data on dispensed prescriptions from health care centres were retrieved from the Swedish prescribed drug register and analysed for September–December 2006 (pre-intervention) and September–December 2007 (post-intervention). All drugs dispensed during each 4 month period were regarded as potentially interacting.


Use of SFINX was associated with a 17% decrease, to 1.81 × 10−3 from 2.15 × 10−3 interactions per prescribed drug-drug pair, in the prevalence of potentially serious drug-drug interactions (p = 0.042), whereas no significant effect was observed in the control group. The change in prevalence of potentially serious drug-drug interactions did not differ significantly between the two study groups. The majority of drug-drug interactions identified were related to chelate formation.


Prescriptions resulting in potentially serious drug-drug interactions were significantly reduced after integration of the drug-drug interaction database SFINX into electronic health records in primary care. Further studies are needed to demonstrate the effectiveness of drug-drug interaction warning systems.

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We thank Kim Raihle for health care center data and Fadi Jazzar and Bengt Sjöborg for development and running of data analysis tool.

Conflicts of interest

M.L. Andersson and Y. Böttiger are, as employees of the Stockholm County Council, working with the quality and content of the SFINX database.

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Correspondence to M. L. Andersson.

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Andersson, M.L., Böttiger, Y., Lindh, J.D. et al. Impact of the drug-drug interaction database SFINX on prevalence of potentially serious drug-drug interactions in primary health care. Eur J Clin Pharmacol 69, 565–571 (2013).

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