Loiasis treatment by diethylcarbamazine (DEC) may be complicated by a meningoencephalitis that is often fatal. Following one case, four others have been reviewed in the literature and the therapeutic approach in resuscitation departments discussed. Until the discovery of other less-dangerous microfilaricidal or macrofilaricidal drugs, we raise the question of the opportunity to treat loiasis by DEC, while many authors consider it as a simple nuisance.