This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Histamine, 5-HT and PGs, Subject name: Pharmacology
Which of the following adverse effects is characteristically associated with methysergide? 
Select and explain. 
A. Pulmonary hypeension, B. Retroperitoneal fibrosis, C. Hepatotoxicity, D. Ischemic hea disease
B: Retroperitoneal fibrosis
Answer: B: Retroperitoneal fibrosis 
Explanation: All ergot derivatives can cause fibrosis on long term use. Due to risk of retroperitoneal fibrosis, methysergide should never be given continuously for more than 6 months.