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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A patient has a frequent tendency of migraine attacks. Which of the following drug should be given as prophylaxis?
assistant
The correct answer is  Prophylaxis of migraine is required if the attacks are frequent (>2-3 per month). The drugs useful for prophylaxis are: 

Propranolol is the most commonly used drug for prophylaxis of migraine attacks.
Timolol, atenolol, metoprolol and nadolol can also be used but the drugs with ISA (e.g. pindolol) are ineffective.