LAUSR

AIM Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but severe mostly drug-induced cutaneous reactions. Acetaminophen is an over-the-counter drug used worldwide to treat pain and reduce fever. In 2013, the US Food and Drug Administration informed the public that acetaminophen was associated with a rare risk of SJS/TEN. The aim of the present retrospective study was to analyse reports of acetaminophen as a possible suspect in the development of SJS/TEN from the French Pharmacovigilance Database (FPDB). METHODS Cases of TEN/SJS with acetaminophen as a suspect drug registered in the FPDB, collected from January 2002 to December 2013, were analysed by an expert group. The algorithm of drug causality for epidermal necrolysis (ALDEN) was used as a reference tool for SJS/TEN to assess the causality of each suspect drug. RESULTS After exclusion of 16 nonvalidated cases, 112 cases (47 TEN, 51 SJS, 14 SJS/TEN overlaps) involving 574 suspected drugs (5⋅1/case) were analysed. In 80 cases, the acetaminophen ALDEN score was inferior or equal to that of other drugs, associated with a higher suspicion for causality. In 32 cases, acetaminophen had the highest score but matched with a 'very unlikely' or 'unlikely' causality in 12 cases. For the 20 remaining cases with a 'possible' or ' probable' causality, a protopathic or a confounding bias was likely in 14 cases. CONCLUSIONS After analysis of the French pharmacovigilance data using the ALDEN algorithm, we found no obvious SJS/TEN risk related to the use of acetaminophen in this large national series.