Final answer:
Visual disturbances are a key manifestation of digoxin toxicity that a nurse should identify when assessing a patient who has been on digoxin. Bradycardia, nausea, and vomiting are also common symptoms of toxicity.
Step-by-step explanation:
When a nurse is collecting data from a client who has been taking digoxin for 1 month, the nurse should identify visual disturbances as a manifestation of digoxin toxicity. Other common signs of digoxin toxicity include bradycardia (slow heart rate), nausea, and vomiting. It is important for healthcare professionals to monitor patients on digoxin for these symptoms, as they can indicate dangerous levels of the medication.