A nurse is caring for a client who has an infection and has been taking penicillin. Which of the following statements by the client should the nurse identify as the priority to report to the provider?

A. "I have vomited several times.": Vomiting can be a side effect of penicillin, but it is usually manageable and not immediately life-threatening unless severe dehydration occurs. B. "I am having diarrhea.": Mild diarrhea is a common side effect of antibiotics. It is important to monitor for signs of C. difficile infection, but occasional loose stools are not immediately critical. C. "I am having trouble swallowing.": Difficulty swallowing may indicate oropharyngeal edema, which can be a sign of a severe allergic reaction to penicillin. This requires immediate attention as it can progress to airway obstruction. D. "My skin feels itchy all over.": Generalized itching may indicate a mild allergic reaction. While it should be monitored, it is less urgent than symptoms suggesting airway compromise.