What instruction should a nurse include for a client receiving sulfisoxazole?

Maintaining a high fluid intake is important for a client receiving sulfisoxazole because this medication is a sulfonamide antibiotic, which can sometimes cause crystal formation in the urine. By ensuring adequate hydration, the nurse helps to dilute the urine, thereby reducing the risk of crystalluria and ensuring that the medication is effectively eliminated from the body. High fluid intake supports kidney function and helps prevent possible complications related to the urinary tract.

In contrast, the other choices do not promote optimal safety or effective use of the medication. Discontinuing the medication when feeling better may lead to incomplete treatment of the infection, potentially resulting in a resurgence of the illness or resistance to the antibiotic. Calling the healthcare provider if urine turns dark brown could be a valid action, but it is a reaction that is not standard guidance compared to the necessity of fluid intake. A decrease in dosage when symptoms improve is not appropriate without a healthcare provider’s direction, as the full course of the antibiotic should typically be completed to ensure the infection is fully resolved.