What is ephedrine primarily used for?

Ephedrine is primarily used in the treatment of asthma due to its bronchodilator properties. It works by stimulating the beta-adrenergic receptors in the lungs, leading to relaxation of bronchial muscles, which helps to open up airways and facilitates better airflow. This makes it particularly effective for patients experiencing bronchoconstriction associated with asthma or other respiratory conditions.

The other options involve medications or treatments that serve very different purposes. For example, depressants typically refer to substances that reduce the activity of the central nervous system, which is not the action of ephedrine. Pain relievers are medications specifically aimed at alleviating pain, whereas ephedrine does not serve this function. Antidepressants are used to treat mood disorders and have no direct connection to the respiratory system or the treatment of asthma, showcasing the distinct role that ephedrine plays in respiratory care.