In an acute asthma attack, which drug provides the fastest bronchodilation?

In an acute asthma attack, which drug provides the fastest bronchodilation?
A. Salmeterol
B. Ipratropium
C. Salbutamol
D. Theophylline

A patient with TB is switched from rifampicin to rifabutin due to drug interactions. Rifabutin’s main advantage is:
A. No effect on CYP enzymes
B. Less potent CYP3A4 induction
C. Greater bactericidal activity
D. Higher oral bioavailability