For which symptom should a client on nitrofurantoin seek immediate medical attention?

A client on nitrofurantoin should seek immediate medical attention for chest pain. This symptom is significant because it may indicate serious conditions such as pulmonary toxicity or a potential allergic reaction, which can occur with nitrofurantoin use. Symptoms of chest pain warrant urgent evaluation as they could suggest complications affecting the heart or lungs, which require prompt medical intervention.

Although headache, diarrhea, and common cold symptoms may be uncomfortable and can occur as side effects, they do not signal an immediate medical emergency. Headaches and diarrhea are often manageable and may just require supportive care, while common cold symptoms, such as cough or mild congestion, typically do not pose an immediate risk to health. It is crucial for clients taking nitrofurantoin to be aware of and report any unusual or serious symptoms, particularly those that could indicate more severe complications like chest pain.