An international comparative study1 on regulatory medicines information conducted in 2002 by WHO, the Mario Negri Research Institute (Milan, Italy), the Institut Catal de Farmacologia, Universitat Aut noma (Barcelona, Spain) and the International Society of Drug Bulletins (Paris, France), showed that medicines recommendations used by prescribers and patients vary considerably between countries. Disagreement was found even within a single country, when written materials from different brands of the same drug were compared. The discrepancies arise because national regulatory authorities do not or may not have the resources to conduct full and systematic assessments of data from clinical studies and post-marketing surveillance, before approving prescribing information materials. The discrepancies are worrying because they can mislead prescribers and patients regarding medicines use, and researchers seeking to compare medicines use patterns across countries.
1 International Comparative Study on Drug Information (ICSODI) Collaborative Group. Prescribing information in 26 countries: a comparative study. European Journal of Clinical Pharmacology, in press.
Summaries of product characteristics, package inserts and data sheets were assessed for 26 countries for ciprofloxacin, fluoxetine and nifedipine. These three medicines were chosen because they were among the top 30 medicines in terms of global sales in 2000, and cover three therapeutic areas of worldwide relevance in terms of mortality and morbidity. For the four variables considered - indications, dosage range in adults, side-effects and cautions - an information checklist was created, using the British National Formulary (BNF).
Out of 26 countries, 11 had information that matched BNF indications for nifedipine. For ciprofloxacin, materials from 3 countries did not match the dose range recommended by the BNF, while for nifedipine and fluoxetine, materials from 7 countries and 9 countries respectively did not match. Also for ciprofloxacin and fluoxetine, none of the materials from the various countries reported all major side-effects listed in the BNF. None of the materials from any of the countries reported all the cautions included in the BNF for nifedipine.