Final answer:
Cromolyn sodium is a commonly prescribed mast cell stabilizer used for asthma. It helps prevent asthma attacks by stabilizing mast cells and preventing the release of histamines.
Step-by-step explanation:
The commonly prescribed mast cell stabilizer used for asthma is cromolyn sodium. Cromolyn sodium helps to prevent asthma attacks by stabilizing mast cells, preventing them from releasing histamines and other chemicals that cause inflammation and narrowing of the airways. This medication is usually used as a preventative measure and needs to be taken regularly to maintain its effectiveness.