The nurse prepares to administer a scheduled dose of labetalol by mouth to a client with hypertension. The client's vital signs are temperature 99° F (37.2° C), heart rate 48 beats/minute, respirations 16 breaths/minute, and blood pressure (B/P) 150/90 mm Hg. Which action should the nurse take?

Choice A rationale: Tetracycline should generally be taken on an empty stomach, as certain food and beverages, including orange juice, can interfere with its absorption. The nurse should instruct the client to take tetracycline with water and on an empty stomach unless otherwise specified by the healthcare provider.

Choice B rationale: Tetracycline is an antibiotic that can make the skin more sensitive to sunlight, leading to an increased risk of sunburn and photosensitivity reactions. To prevent these adverse effects, the nurse should instruct the client to protect their skin from sunlight while taking the medication. This includes using sunscreen, wearing protective clothing, and avoiding prolonged sun exposure. It is essential to educate the client about this potential side effect to ensure their safety and minimize skin reactions during treatment.

Choice C rationale: Tetracycline does not require routine monitoring of serum drug levels. It is an antibiotic with a well-established dosing regimen, and monitoring drug levels is not necessary for its safe and effective use.

Choice D rationale: While taking tetracycline with milk or antacids may help reduce GI irritation, it can also interfere with the absorption of the medication. Therefore, it is generally recommended to take tetracycline with water and on an empty stomach to ensure optimal absorption and effectiveness.

Choice A rationale: Ingestion of Wort can reduce the client's intake of sodium: This information is not directly related to the situation of a renal transplant and graft rejection. It is not the most significant finding regarding the use of St. John's Wort in this context.

Choice B rationale: Adding the herb decreases the need for corticosteroids: There is no evidence or indication that St. John's Wort can decrease the need for corticosteroids, especially in the context of a renal transplant and graft rejection.

Choice C rationale: While St. John's Wort is sometimes used as an herbal remedy for depression, the most significant information, in this case, is its potential to interact with cyclosporine and affect the client's immunosuppressive medication. The focus should be on the drug interaction and the risk it poses to the client's graft health, rather than the reason for using the herb.

Choice D rationale: The most significant information about the finding that the client has been self-administering St. John's Wort is that it can decrease plasma concentrations of cyclosporine. Cyclosporine is an immunosuppressive medication commonly used after a renal transplant to prevent graft rejection. When St. John's Wort is taken concurrently with cyclosporine, it can induce certain liver enzymes responsible for drug metabolism, leading to a decreased concentration of cyclosporine in the bloodstream. This can potentially reduce the effectiveness of cyclosporine in preventing graft rejection, putting the client's transplanted kidney at risk.