Retroperitoneal fibrosis has developed in three patients who were taking methysergide maleate (Sansert). This experience does not interdict use of the drug, but such potential mechanical involvement of ureteral function would make the use of methysergide unattractive in the presence of known renal disease. After a year of receiving methysergide, the patient should discontinue taking it for at least three months and undergo suitable tests. Both patient and doctor should be alert for any evidence of retroperitoneal fibrosis.
Utz DC, Rooke ED, Spittell JA, Bartholomew LG. Retroperitoneal Fibrosis in Patients Taking Methysergide. JAMA. 1965;191(12):983-985. doi:10.1001/jama.1965.03080120017005