Final answer:
The primary nursing care for clients on hydroxychloroquine is monitoring for visual changes, as the medication can cause retinopathy and potentially lead to vision impairment.
Step-by-step explanation:
The priority nursing care for a client who is prescribed hydroxychloroquine (Plaquenil) is monitoring for visual changes. Hydroxychloroquine is known to potentially cause retinopathy, which may lead to vision impairment. Regular eye exams are recommended to detect any changes in vision as early as possible. While ensuring the medication is taken with food and assessing for gastrointestinal side effects are important, they do not take precedence over the potential risk to the client's vision. Administering the medication at bedtime is not necessarily a priority unless it is to manage side effects that can interfere with sleep.