This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
[{'content': 'Which of the following Fibrinolytic is antigenic? \nSelect and explain. \nA. Urokinase, B. Alteplase, C. Tenecteplase, D. Streptokinase', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The clinically important fibrinolytic are:\n1. Streptokinase\n2. Urokinase\n3. Alteplase (rt-PA)\n4. Reteplase\n5. Tenecteplase\nStreptokinase:\n\nIt is obtained from Beta hemolytic Streptococci group C.\nIt is inactive as such: combines with circulating plasminogen to form an activator complex which then causes limited proteolysis of other plasminogen molecules to plasmin.\nAntistreptococcal antibodies present due to past infections inactivate a considerable fraction of the initial dose of Stk: a loading dose is necessary for the beginning. Its t1/2\xa0is estimated to be 30-80 min.\nStreptokinase is antigenic; can cause hypersensitivity reactions and anaphylaxis, especially when used second time in a patient.\nRepeat doses are also less effective due to neutralization by antibodies. Fever is common, hypotension and arrhythmias are reported.', 'role': 'assistant'}]