olodaterol + ketoconazole

**Olodaterol + ketoconazole** is not a marketed fixed-dose combination or branded medication but refers to the coadministration of the two separate drugs: **olodaterol**, a long-acting beta2-adrenergic agonist used as a bronchodilator for the maintenance treatment of chronic obstructive pulmonary disease (COPD), and **ketoconazole**, a potent antifungal agent and strong CYP3A4 enzyme inhibitor. Olodaterol acts by activating beta2-adrenergic receptors in airway smooth muscle, resulting in bronchodilation through increased cyclic AMP[2][4][7]. Ketoconazole works by inhibiting fungal ergosterol synthesis via inhibition of cytochrome P450-dependent lanosterol 14-alpha-demethylase[8]. **When both drugs are coadministered, ketoconazole significantly increases systemic exposure to olodaterol (Cmax by 66%, AUC by 68%) owing to CYP3A4 inhibition, which may enhance both bronchodilator effects and the risk of olodaterol-related side effects such as cardiovascular events and hypokalemia[1][5][6][9].** Caution is advised when using this drug combination.