Mesna

Mesna, sold under the brand name Mesnex among others, is a medication used in those taking cyclophosphamide or ifosfamide to decrease the risk of bleeding from the bladder.[1] It is used either by mouth or injection into a vein.[1] Common side effects include headache, vomiting, sleepiness, loss of appetite, cough, rash, and joint pain.[1] Serious side effects include allergic reactions.[1] Use during pregnancy appears to be safe... [wikipedia]