A client with a history of kidney stones is prescribed allopurinol. The nurse should recognize that this medication is primarily used to:

A. Uric acid stones may cause pain, but they do not typically present with costovertebral angle tenderness. Uric acid stones are more likely to be associated with gout and hyperuricemia.

B. Calcium oxalate stones are common and can cause pain, but they do not typically cause costovertebral angle tenderness. They are more likely to cause localized pain in the back or side.

C. This is the correct answer. Struvite stones, also known as infection stones, can cause severe pain that radiates to the back and lower abdomen. They are often associated with urinary tract infections, and the presence of an infection can lead to costovertebral angle tenderness.

D. Cystine stones are rare and are more likely to cause chronic, dull pain rather than sudden and severe pain with tenderness.

A. Limiting fluid intake to 1 liter per day is not recommended to prevent kidney stone formation. Adequate hydration is essential to

help prevent stone formation, as it helps dilute the urine and reduce the concentration of minerals that can lead to stone formation.

B. Decreasing dietary fiber intake is not a preventive measure for kidney stones. In fact, increasing dietary fiber intake can be beneficial for overall health.

C. Reducing calcium intake from all sources is not recommended to prevent kidney stones. In some cases, reducing dietary calcium intake can actually increase the risk of certain types of kidney stones.

D. This is the correct answer. Increasing citric acid intake can help prevent certain types of kidney stones, such as calcium oxalate stones. Citric acid helps to bind calcium in the urine, reducing the risk of stone formation. Citric acid can be found in citrus fruits and juices, and the nurse may advise the client to include more of these foods in their diet.