This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hypeension, Arrhythmias, Dyslipidemia, Subject name: Pharmacology
[{'content': 'Tolazoline is:- \nSelect and explain. \nA. Thrombin inhibitor, B. Vasodilator, C. Vasoconstrictor, D. Antispasmodic', 'role': 'user'}, {'content': "Answer: B \nExplanation: Phentolamine and Tolazoline are non-selective alpha blockers. Cause vasodilation in peripheral vessels Used in Raynaud's disease and enhance angiography in peripheral vessels Alpha 1 agonist (Phenylephrine) are vasoconstrictors. Anticholinergic drugs like dicyclomine are used as antispasmodics. Indirect thrombin inhibitors: Heparin, LMWH, Fondaparinux, Danaparoid. Direct thrombin inhibitors: Lepirudin, Bivalrudin, Argatroban", 'role': 'assistant'}]