This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Pharmacology
The following drug is NOT useful during acute attack of bronchial asthma: 
Select and explain. 
A. Salbutamol, B. Hydrocoisone, C. Cromolyn sodium, D. Theophylline
C: Cromolyn sodium
Answer: C: Cromolyn sodium 
Explanation: drugs used in an acute attack of asthma a) hydrocoisone b)salbutamol c)oxygen d)antibiotic (intensive), IV theophylline cromolyn sodium, nedocromil-mast cell stabilizers are used in chronic asthma ESSENTIALS OF MEDICAL PHARMACOLOGY SEVENTH EDITION KD TRIPATHI PG NO.233