From the Research
Yes, bicarbonate levels can increase with Lasix (furosemide) administration, as evidenced by the most recent study 1 which highlights the potential for severe hypokalemia and metabolic alkalosis with furosemide use. Lasix is a loop diuretic that primarily acts by inhibiting sodium and chloride reabsorption in the ascending loop of Henle in the kidneys. When Lasix blocks the sodium-potassium-chloride cotransporter, it causes increased excretion of chloride relative to bicarbonate. This disproportionate loss of chloride can lead to a metabolic alkalosis, characterized by elevated serum bicarbonate levels. Additionally, Lasix causes volume contraction, which stimulates the kidneys to reabsorb more sodium and, consequently, more bicarbonate, further contributing to the rise in bicarbonate levels. This effect is particularly notable with higher doses or prolonged use of Lasix, as seen in cases of furosemide abuse 2 or therapeutic use 3. Patients with heart failure, liver cirrhosis, or other conditions requiring chronic diuretic therapy should have their electrolytes and acid-base status monitored regularly, as persistent metabolic alkalosis can cause symptoms like confusion, muscle twitching, and cardiac arrhythmias, as reported in various studies 1, 2, 3. It is essential to consider the potential for metabolic alkalosis when prescribing Lasix, especially in patients with underlying conditions that may predispose them to electrolyte imbalances, and to monitor their electrolyte levels and acid-base status closely to prevent complications. The study by 1 emphasizes the importance of monitoring electrolyte levels in patients taking furosemide, as even mildly symptomatic patients can have severe hypokalemia and metabolic alkalosis. In clinical practice, it is crucial to weigh the benefits of Lasix against the potential risks of metabolic alkalosis and to take steps to mitigate these risks, such as monitoring electrolyte levels and adjusting the dose or discontinuing the medication as needed. Overall, the evidence suggests that bicarbonate levels can increase with Lasix administration, and clinicians should be aware of this potential side effect and take steps to monitor and manage it.