A client receives the wrong medication. The nurse who made the medication error should do which of the following first?

In the event of a medication error, the immediate priority is the safety and well-being of the client. Observing the client allows the nurse to assess for any adverse reactions or side effects resulting from the administration of the wrong medication. This step is crucial because it helps ensure that any potential harm is identified and addressed promptly. Correctly assessing the client's condition provides critical information that can guide further actions, such as notifying the healthcare provider about the situation.

While it is important to document the error, inform the healthcare provider, and report the incident, these actions should follow the initial assessment of the client. The health and safety of the client is the primary concern in any emergency or unexpected situation. After ensuring the client is stable and any immediate risks are managed, the nurse can then proceed with the appropriate reporting and documentation procedures.