The nurse administers acetylcysteine to a client with thick mucous and a nonproductive cough. To evaluate the effectiveness of the medication, which question should the nurse ask the client?

Rationale: A. "What color is the mucous?": Asking about the color of mucus helps identify infection, but it does not measure whether acetylcysteine has been effective. The primary action of this medication is to loosen and thin secretions, not change their color. B. "Are you experiencing any pain when you cough?": Pain assessment is important for client comfort, but it is not directly related to the therapeutic effect of acetylcysteine. The drug’s goal is to improve secretion clearance, not reduce coughing discomfort. C. "How much phlegm are you coughing up?": Acetylcysteine is a mucolytic that decreases mucus viscosity, making it easier to expectorate. Evaluating whether the client is producing more phlegm provides the best measure of medication effectiveness in clearing secretions. D. "Are you still coughing?": Coughing may still occur because it is part of the mechanism for clearing mucus from the airways. The presence or absence of coughing does not reliably indicate whether acetylcysteine is improving secretion mobilization.