[Number and nature of drug interactions concerning antineoplastic drugs]

Antineoplastic drugs are prone to drug-drug interactions. Cancer patients often receive multiple concurrent medications and health care professionals are not always aware that patients are also taking others treatments. The aim of this study was to assess the number of drug-drug interactions of antineoplastic drugs used in solid tumours and to find out and collect recommendations for each of them. We performed a bibliographic search from the Vidal dictionary, the "thesaurus de l'Afssaps", the "dossier du CNHIM" and from literature of scientific journals. For the 40 antineoplastic drugs studied, 726 drug-drug interactions were identified; 186 from the Vidal dictionary, 356 from scientific literature and 184 from others bibliographic sources. The most frequently involved antineoplastic drugs are ifosfamide, paclitaxel and erlotinib. The ATC groups of associated drugs are antiinfectives for systemic use, alimentary tract and metabolism and nervous system. Antiretrovirals are prone to drug interactions with antineoplastic drugs, particularly ritonavir, tipranavir and efavirenz. 7 contraindications and 15 unadvised associations were held. For 58% of interactions, no management recommendation was specified in the bibliographic source. Healthcare professionals must be aware that the Vidal dictionary gave information for only 26 % of registered drug-drug interactions. Our database gather in one document drug-drug interactions that come from different bibliographic sources. The setting of this database is part of the multidisciplinary caring of cancer patient. Drug-drug interaction is a field which for physicians and pharmacists should developed collaboration for patient care.