Advice on Drug Safety in Pregnancy

Abstract

Safety regarding use in pregnancy is not established for many drugs. Inconsistencies between sources providing drug information can give rise to confusion with possible therapeutic consequences. Therefore, it is important to measure clinically important differences between drug information sources. The objective of this study was to compare two easily accessible Norwegian sources providing advice on drug safety in pregnancy - the product monographs in the Felleskatalog (FK), published by the pharmaceutical companies, and the five regional Drug Information Centres (DICs) in Norway - in addition to assessing the frequency of questions regarding drug safety in pregnancy made to the DICs according to the Anatomical Therapeutic Chemical (ATC) classification system. Advice on drug use in pregnancy provided by the DICs in 2003 and 2005 were compared with advice in the product monographs for the respective drugs in the FK. Comparison of advice was based on categorization to one of four categories: can be used, benefit-risk assessment, should not be used, or no available information. A total of 443 drug advice were categorized. Seven out of ten of drugs frequently enquired about, according to the ATC system, were drugs acting on the nervous system (group N). For 208 (47%) of the drugs, advice differed between the DICs and FK. Advice from the FK was significantly (p < 0.01) more restrictive than advice from the DICs. There were no differences in the level of consistency of advice between drugs that were newly introduced and those that had been on the market for a longer time, advice regarding use of drugs in the first trimester and advice regarding use of drugs in the second or third trimester, or between advice provided during 2003 and during 2005. The results of this study show considerable differences between two Norwegian sources providing advice on the use of drugs in pregnancy. Based on the knowledge that healthcare providers choose sources of information in a random manner, our results may be of clinical importance. We believe that the problem with heterogeneous drug information on this subject is not confined to Norway and that our results should be of international interest.