Which of the following is NOT considered a rescue inhaler?

Budesonide is not considered a rescue inhaler because it is a corticosteroid used primarily to manage and control inflammation in the airways over time. It is intended for long-term asthma treatment rather than immediate relief from acute asthma symptoms. This type of medication reduces swelling and mucus production in the airways, helping to prevent asthma attacks rather than providing rapid relief during an attack.

In contrast, the other options—ipratropium, formoterol, and salbutamol—are all classified as rescue medications. Ipratropium is an anticholinergic agent that acts quickly to relieve bronchospasm, while salbutamol is a short-acting beta-agonist specifically designed for rapid relief of asthma symptoms. Formoterol, although typically a long-acting beta-agonist, can also provide relief for acute symptoms under certain circumstances. Therefore, they are utilized during asthma exacerbations or acute episodes to achieve immediate bronchodilation and alleviate symptoms.