<prompt> Long acting beta agonist used once a day:SalmeterolFormoterolIndacaterolTerbutaline  <response>: Ans. C. IndacaterolRef: Katzungs Basic and Clinical Pharmacology 13thed, p340ExplanationAns. c. Indacaterol Ref: Katzungs Basic and Clinical Pharmacology 13thed, p340Explanationb agonistFeatures Albuterol salbutamol Terbutaline Metaproterenol Pirbuterol Metered-dose inhalers Bronchodilation is maximal within 15-30 minutes and persists for 3-4 hours.Frequent administrations required based on clinical status. Can be given by nebulizer if using metered dose is not possible. Albuterol and terbutaline are also available in tablet form 2 to 3 times daily option d, no added advantage therefore prescribed rarely. Only terbutaline is available for subcutaneous injection; useful in severe asthma requiring emergency treatment when aerosolized therapy is not available or has been ineffective; CAUTION: Due to its longer duration of action cumulative effects may be seen after repeated injections.Bambuterol It is prodrug of terbutaline. Slowly hydorlyzed by pseudocholinesterase to release the active drug over a period of 24 hours. Available in tablet form and given once daily.Long acting: Salme-Terol Formoterol Arformoterol Carmoterol Salmeterol a partial agonist and formoterol a full agonist. Duration of action: 12 hours or more; used 2 times daily options a,b,e. In asthma should not be used as monotherapy; interact with inhaled corticosteroids to improve asthma control.Indacaterol Ultra long acting p2 agonist; used once daily Answer Approved for once daily long-term treatment of COPD and not for asthma and not for acute exacerbations of COPD. 