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What is Which of the following drug is a long-acting beta-2 agonist and explain in detail?
ref; KD Tripathi Pharmacology 7th edition(page no;223) Salmeterol is the first long-acting selective beta 2 agonist with a slow onset of action; used by inhalation on a twice-daily schedule for maintenance therapy and for nocturnal asthma, but not for acute symptoms. salbutamol can be used for acute symptoms