For patients without a clear cause but no red flag findings, many clinicians empirically begin treatment for postnasal drip (eg, antihistamine and decongestant combinations, nasal corticosteroid sprays, or nasal muscarinic antagonist sprays), airway hyperreactivity (eg, inhaled corticosteroid or short-acting beta-adrenergic agonist), or gastroesophageal reflux disease (eg, proton pump inhibitors, H2 blockers).