This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Acute coronary syndrome, Subject name: Medicine
Tadalafil is contraindicated in? 
Select and explain. 
A. Pulmonary aery hypeension, B. Chronic stable angina (acute episode), C. Active infections, D. Hepatic dysfunction
B: Chronic stable angina (acute episode)
Answer: B: Chronic stable angina (acute episode) 
Explanation: Tadalafil is C/I with NTG which is taken for acute attack of angina as in this case. Tadalafil- Uses: For erectile dysfunction For symptoms of BPH Nitrates should not be used within 24 hours of sildenafil, tadalafil, or vardenafil (may produce severe hypotension) Nitrates- C/I in the presence of hyperophic CMP or severe Aoic Stenosis MC side effect of nitrate treatment is headache Hypotension may occur in hypovolemic patients. Development of tolerance To avoid nitrate tolerance, a daily 8 to 12 hour interval free of nitrate exposure is recommended