Halitosis was reported in 29 studies 4, 9, 16, 19, 29, 30, 35, 42, 43, 45, 50, 52, 55, 57, 58, 66– 68, 79, 83, 85, 88, 94, 95, 97, 98, 109, 112, 113. In five studies, patients discontinued treatment due to halitosis 9, 45, 83, 94. In five studies, all patients experienced halitosis 9, 45, 83, 94. Unlike halitosis, other gastrointestinal side effects were reported more often when DMSO was administered intravenously, than transdermally or intravesically.