A patient treated for refractory migraine with methysergide for over a year develops progressive flank pain, raised creatinine and hydronephrosis on imaging. The complication best explained by the drug is:

• A Retroperitoneal fibrosis encasing the ureters ✓
• B Analgesic nephropathy with papillary necrosis
• C Chronic interstitial nephritis from immune complex deposition
• D Renal artery stenosis from intimal hyperplasia

Explanation

Methysergide, a 5-HT2 antagonist used historically for migraine prophylaxis, causes retroperitoneal, pleural and cardiac valvular fibrosis with prolonged continuous use, typically after months to years of therapy. The fibrotic mass encases the ureters, producing obstructive uropathy and rising creatinine. Drug holidays were advised to reduce this risk, and the drug has largely fallen out of use. Papillary necrosis is linked to analgesic abuse, not methysergide, and the other options are not recognised effects.

Reference: Goodman and Gilman's The Pharmacological Basis of Therapeutics, 14th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.