Does furosemide (Lasix) help with hypercalcemia?

From the Guidelines

Lasix (furosemide) can be used to help manage hypercalcemia, but it is not the first-line treatment, and its use should be guided by the most recent clinical practice guidelines, such as those from the National Comprehensive Cancer Network (NCCN) 1. Furosemide works by increasing calcium excretion through the kidneys, which can help lower elevated calcium levels in the blood. Typical dosing for hypercalcemia management ranges from 20-40mg IV every 1-4 hours, depending on the severity of hypercalcemia and the patient's response. However, it's crucial to ensure the patient is adequately hydrated before administering Lasix, as volume depletion can worsen hypercalcemia. Normal saline infusion (typically 200-300 mL/hour) should precede furosemide administration to expand intravascular volume and promote calcium excretion. Some key points to consider in the management of hypercalcemia include:

• Ensuring adequate hydration to prevent volume depletion
• Using loop diuretics like furosemide judiciously and only after hydration has been established
• Considering other treatments like bisphosphonates, calcitonin, or addressing the underlying cause of hypercalcemia for more definitive management
• Following the most recent guidelines for the management of hypercalcemia, such as those provided by the NCCN 1, which recommend hydration, bisphosphonates, denosumab, steroids, and/or calcitonin as primary treatments for hypercalcemia. It's also important to note that while furosemide can be helpful in managing hypercalcemia, it is not a substitute for addressing the underlying cause of the condition, and other treatments may be more effective for long-term management. The NCCN guidelines from 2023 1 provide the most recent recommendations for the management of hypercalcemia, and these should be consulted for the most up-to-date guidance on treatment. In terms of specific treatment approaches, the guidelines recommend:
• Hydration as the first step in managing hypercalcemia
• Bisphosphonates, such as zoledronic acid, as a primary treatment for hypercalcemia
• Denosumab, steroids, and/or calcitonin as additional treatment options
• Furosemide as a loop diuretic to increase calcium excretion, but only after hydration has been established. Overall, the management of hypercalcemia requires a comprehensive approach that addresses the underlying cause of the condition, ensures adequate hydration, and utilizes a range of treatment options as needed. The use of Lasix (furosemide) should be guided by the most recent clinical practice guidelines and should be part of a broader treatment strategy that prioritizes hydration, bisphosphonates, and other primary treatments for hypercalcemia 1.

From the FDA Drug Label

Furosemide may lower serum levels of calcium (rarely cases of tetany have been reported) The answer to whether lasix (furosemide) helps with hypercalcemia is no, as it may actually lower serum levels of calcium. This is relevant for patients with hypercalcemia, as furosemide may not be suitable for treating this condition. In fact, it could potentially worsen hypocalcemia. Key points to consider:

• Furosemide can decrease calcium levels
• It is not indicated for treating hypercalcemia
• Patients with hypercalcemia should be monitored closely when taking furosemide 2 2

From the Research

Hypercalcemia Treatment

• Hypercalcemia can be treated with various methods, including hydration, loop diuretics, calcitonin, and bisphosphonates 3, 4, 5.
• Loop diuretics, such as furosemide (also known as Lasix), may be required in individuals with renal insufficiency or heart failure to prevent fluid overload 3.
• However, a study found that furosemide did not have a significant additional effect on calcium levels in patients with severe hypercalcemia secondary to primary hyperparathyroidism when compared to saline hydration alone 5.

Lasix (Furosemide) Use

• Furosemide is a loop diuretic that can help increase calcium excretion in the urine 5.
• However, its use in treating hypercalcemia is generally limited to patients with renal insufficiency or heart failure, and it is not considered a primary treatment for hypercalcemia 3, 5.
• In a study of patients with severe hypercalcemia secondary to primary hyperparathyroidism, furosemide resulted in a serum calcium increase of 0.09 ± 0.21 mmol/L, and calcium levels did not reach the normal range in any patient 5.

Alternative Treatments

• Intravenous bisphosphonates, such as zoledronic acid, are considered first-line treatments for hypercalcemia 4, 5, 6.
• Glucocorticoids may be used as primary treatment when hypercalcemia is due to excessive intestinal calcium absorption (vitamin D intoxication, granulomatous disorders, some lymphomas) 3, 4.
• Denosumab may be used for bisphosphonate-refractory hypercalcemia and in patients with renal failure 6.