What medication is indicated for reversal of narcotic intoxication?

Even in healthy young subjects, regional differences in pulmonary ventilation and blood flow result in the PaO2 being lower than the PAO2. Why is this so?

a. Most blood flows through the apexes of the lung. b. Most blood flows through areas with high. c. Most blood flows through the bases of the lung. d. Most ventilation goes to the apexes of the lung.

Which of the following medications is an example of a xanthine derivative?

theophylline salmeterol terbutaline epinephrine