Expectorants

(M1.PL.15.75) After receiving a positive newborn screening result, a 2-week-old male infant is brought to the pediatrician for a diagnostic sweat test. The results demonstrated chloride levels of 65 mmol/L (nl < 29 mmol/L). Subsequent DNA sequencing revealed a 3 base pair deletion in a transmembrane cAMP-activated ion channel known to result in protein instability and early degradation. The physician discusses with the parents that the infant will develop respiratory infections due to improper mucus clearance and reviews various mucolytic agents, such as one that cleaves disulfide bonds between mucus glycoproteins thereby loosening the mucus plug. This mucolytic can also be used as a treatment for which of the following overdoses?

(M1.PL.13.9) A 5-year-old Caucasian boy presents with a productive cough that yields thick sputum. His past medical history is significant for three prior pulmonary infections, two of which cultured S. aureus and one that was positive for Pseudomonas. Chest radiograph today is shown in Figure A. Which of the following pharmacologic agents act most directly to counteract the defective physiologic process in these patients?