RESUMEN
OBJECTIVES: The aim of this study was to evaluate the French use, misuse and abuse/dependence of non-injectable forms of fentanyl (transdermal and transmucosal fentanyl formulations). METHODS: Problematic use of transdermal and transmucosal fentanyl formulations was evaluated using an approach combining multiple sources of information: (1) spontaneous notifications recorded during 6 years (2010-2015) for transdermal fentanyl form and 3 years for transmucosal fentanyl forms and (2) data from annual epidemiological systematic surveys conducted by the French Addictovigilance Network during 6 years (2010-2015). RESULTS: In all, 147 cases were notified for transdermal fentanyl formulation and 109 cases for transmucosal fentanyl formulations. According to the galenic formulation, analysis of these cases emphasizes different profiles: for transdermal fentanyl formulation, two consumption profiles: 1/mainly for analgesic effects (74 %): women (61 %), 47 years, with addictive and/or psychiatric history (46 %), treated for chronic non-cancer related pain (93 %), 2/seeking positive psychic effects other than analgesia (26 %): men (82 %), 32 years, with addictive and/or psychiatric history (87 %) and having obtained the fentanyl patch illegally (60 %) for non-medical use. For transmucosal fentanyl formulations, only one consumption profile was observed: women (52 %), 48 years, with addictive (24 %) and/or psychiatric history (28 %), off label indication (72 %) (indications for non-cancer pain and/or no or insufficient opioid background treatment). The misuse of transmucosal fentanyl formulations implies a high risk of adverse effects: those already known of opioid-based drugs, sometimes lethal (withdrawal syndrome, respiratory and central nervous system depression ) but also serious reactions at the application site (buccal or nasal). For the transdermal fentanyl formulation, 27 cases (18 %) of involuntary intoxication were observed, of which 25 were serious. Nineteen deaths involving both forms of fentanyl have been reported (2 for the transmucosal formulations and 17 for the transdermal formulation). CONCLUSION: Our results report significant and worrying misuse of transmucosal fentanyl formulations with wide off-label use and also primary dependence on fentanyl, regardless of galenic formulation, in patients treated for chronic non cancer pain. Given the significant risks of fentanyl, it is necessary to continue the monitoring of misuse, in particular, thanks to the activities of the French Addictovigilance network allowing a multisource approach and who provides information concerning cases of abuse, misuse and dependence.
