The nurse is caring for a client who has an order for no food or drink by mouth and is receiving intravenous acyclovir. To prevent nephrotoxicity, what is the nurse's action?

A) Hold metformin 24 hours to 48 hours before the CT. This is correct because it reduces the chance of metformin accumulating in the blood and causing lactic acidosis when combined with the contrast dye.

B) Hold metformin 48 hours after the CT. This is also correct because it allows time for the contrast dye to be eliminated from the body before resuming metformin.

C) Double the metformin dose after the CT. This is incorrect and dangerous because it can cause hypoglycemia, low blood sugar, which can lead to confusion, seizures, coma, or death. D) Take metformin as scheduled the day of the CT. This is incorrect and risky because it can result in high levels of metformin in the blood when mixed with the contrast dye, increasing the likelihood of lactic acidosis.

E) Resume metformin at half dose after the CT. This is incorrect and unnecessary because there is no evidence that reducing the dose of metformin after a CT scan with contrast dye has any benefit or reduces any harm.

a. This is the correct answer because maintaining adequate hydration helps prevent nephrotoxicity associated with acyclovir. Encouraging fluid intake during and after the infusion helps flush the drug through the kidneys.

b. While monitoring urinary output is important, it alone may not be sufficient to prevent nephrotoxicity.

c. Providing a low-protein diet is not a standard intervention for preventing acyclovir-induced nephrotoxicity.

d. Administering intravenous normal saline boluses, as ordered, can help maintain hydration and prevent nephrotoxicity. However, encouraging oral fluid intake is a more direct and immediate measure during acyclovir infusion.