Mapenterol hydrochloride is an analytical control substance with 98% purity, utilized in laboratory and pharmaceutical quality control for calibration, research, and analytical purposes. It is a selective beta-2 adrenergic agonist primarily employed as a bronchodilator in the management of respiratory conditions such as asthma and chronic obstructive pulmonary disease (COPD). It relaxes the smooth muscles of the airways, improving airflow and reducing symptoms like wheezing, shortness of breath, and chest tightness. Its selectivity minimizes cardiac side effects compared to non-selective agents. It is often administered via inhalation for rapid onset and lower systemic exposure, making it suitable for maintenance therapy rather than acute relief.