Final answer:
A bronchodilator is a medication used to relax and open the airways in the lungs, making it easier to breathe during asthma attacks.
Step-by-step explanation:
A medication that relaxes and expands the bronchial passages into the lungs is a bronchodilator. This type of medication is often used to treat asthma by opening airways wider. Unlike antibiotics, which target infections, or antihistamines and anti-inflammatory drugs, which reduce allergic reactions and inflammation, bronchodilators work by soothing constricted air passages and helping to re-expand them, which facilitates easier breathing. These medications typically start to take effect almost immediately and are crucial during an asthma attack to alleviate symptoms such as wheezing and chest tightness.