When discharging a client receiving trimethoprim-sulfamethoxazole, what is an essential instruction?

Drinking 8 to 10 glasses of water per day is essential for clients receiving trimethoprim-sulfamethoxazole because this medication can lead to crystalluria, which is the formation of crystals in the urine. Adequate hydration helps to dilute the urine and prevent the crystallization of the drug, thereby reducing the risk of kidney damage and ensuring proper elimination of the medication from the body.

Ensuring proper fluid intake is crucial, especially since trimethoprim-sulfamethoxazole can concentrate in the renal tubules, and sufficient hydration promotes effective renal function. This instruction contributes to overall safety and efficacy during treatment.

The other choices either introduce risks or do not apply specifically to the medication's use. For instance, limiting fluid intake would increase the risk of precipitation of solids in urine, which is detrimental. While taking the medication with food may be helpful for some patients to minimize gastrointestinal side effects, it is not as critical as ensuring proper hydration. Monitoring blood sugar levels weekly is not relevant for this medication, as trimethoprim-sulfamethoxazole does not significantly affect glucose metabolism directly.