Macrolides

Which of the following is the primary mechanism of action of macrolide antibiotics?

Among the macrolide antibiotics, which is the most common cause of drug-drug interactions due to cytochrome P450 enzyme inhibition?

A 28-year-old man with atypical pneumonia (suspected *Mycoplasma pneumoniae*) is started on azithromycin 500 mg once daily. On day 5, he develops palpitations, dizziness, and syncope. ECG shows a prolonged QTc interval of 520 ms (baseline 400 ms). Serum potassium is 3.2 mEq/L (normal 3.5–5.0). What is the most appropriate immediate next step?

A 32-year-old woman with community-acquired pneumonia is being treated with either erythromycin or azithromycin. Which pharmacokinetic property best differentiates azithromycin from erythromycin in clinical practice?

Azithromycin differs from erythromycin in which of the following pharmacokinetic properties?