The nurse is caring for a client with neurogenic diabetes insipidus and administers what drug to treat the condition.

Guaifenesin is an expectorant that helps thin and loosen mucus in the lungs, making it easier to cough up the sputum. Some possible explanations for the other choices are:

Choice A. Benzonatate is wrong because benzonatate is an antitussive that suppresses the cough reflex by numbing the throat and lungs.

It does not help with sputum production or clearance.

Choice B. Dextromethorphan is wrong because dextromethorphan is also an antitussive that acts on the brain to reduce the urge to cough.

It does not affect the mucus or bronchial secretions.

Choice C. Hydrocodone is wrong because hydrocodone is a narcotic antitussive that works by binding to opioid receptors in the brain and spinal cord, blocking pain signals and decreasing cough.

It can cause sedation, respiratory depression, and dependence, and is not indicated for bronchitis.

Normal ranges for sputum production vary depending on the individual and the cause of the cough, but generally range from 10 to 100 mL per day.

Excessive or abnormal sputum may indicate an infection, inflammation, or obstruction of the airways.

Famotidine is a histamine type 2 receptor antagonist (H blocker) which is commonly used for treatment of acid-peptic disease and heartburn. Famotidine has been linked to rare instances of clinically apparent acute liver injury, but it is less likely to cause hepatotoxicity than cimetidine, another H blocker. Famotidine also has fewer drug interactions than cimetidine.

Choice A is wrong because nizatidine is another H blocker that can cause mild and transient serum aminotransferase elevations.

Nizatidine has not been linked to cases of clinically apparent liver injury, but it has not been widely used.

Choice B is wrong because ranitidine is another H blocker that can cause mild and transient serum aminotransferase elevations.

Ranitidine has also been associated with rare instances of clinically apparent liver injury, some of which were fatal or required liver transplantation.

Choice C is wrong because cimetidine is another H blocker that can cause mild and transient serum aminotransferase elevations.

Cimetidine has also been implicated in several cases of clinically apparent acute liver injury, some of which were severe and led to acute liver failure and death.

Cimetidine also has many drug interactions due to its inhibition of cytochrome P enzymes.

Normal ranges for serum aminotransferases are 7 to 56 U/L for alanine aminotransferase (ALT) and 10 to 40 U/L for as