From the Guidelines
Lasix (furosemide) should be used cautiously or temporarily held in patients with hypotension, as it can worsen low blood pressure, and alternative approaches such as reducing the dose or switching to continuous infusion should be considered to minimize the risk of further decreasing cardiac preload and worsening hypotension. When systolic blood pressure falls below 90 mmHg, consider withholding Lasix doses until blood pressure stabilizes, as recommended by the 2016 ESC guidelines for the diagnosis and treatment of acute and chronic heart failure 1. If Lasix is essential for managing fluid overload, reduce the dose by 50% or switch to continuous infusion at 1-5 mg/hour rather than bolus dosing, and ensure adequate intravascular volume before administering Lasix. It is also crucial to monitor blood pressure, urine output, and electrolytes closely during therapy, as diuretic therapy can cause worsening renal function, which is associated with increased mortality among acute heart failure syndrome patients 1. The mechanism behind this caution is that Lasix causes diuresis and natriuresis, reducing intravascular volume which can further decrease cardiac preload and worsen hypotension. In patients with heart failure, this can be particularly problematic as they rely on adequate preload for cardiac output. Alternative approaches include temporarily using thiazide diuretics which have less profound diuretic effects, or addressing the underlying cause of hypotension before resuming diuretic therapy. Once blood pressure improves to >100 mmHg systolic, Lasix can typically be restarted at a lower dose with careful monitoring.
Some key considerations when using Lasix in patients with hypotension include:
- Monitoring blood pressure, urine output, and electrolytes closely during therapy
- Ensuring adequate intravascular volume before administering Lasix
- Reducing the dose or switching to continuous infusion to minimize the risk of further decreasing cardiac preload and worsening hypotension
- Temporarily using thiazide diuretics which have less profound diuretic effects
- Addressing the underlying cause of hypotension before resuming diuretic therapy
It is essential to note that the "best dose" of diuretic is likely to be different for each patient, and diuretic therapy, when prescribed, requires careful titration to promote effective diuresis while avoiding worsening renal function, as highlighted in the 2007 clinical policy for the evaluation and management of adult patients presenting to the emergency department with acute heart failure syndromes 1.
From the FDA Drug Label
As with any effective diuretic, electrolyte depletion may occur during Furosemide tablets therapy, especially in patients receiving higher doses and a restricted salt intake Hypokalemia may develop with Furosemide tablets, especially with brisk diuresis, inadequate oral electrolyte intake, when cirrhosis is present, or during concomitant use of corticosteroids, ACTH, licorice in large amounts, or prolonged use of laxatives. All patients receiving Furosemide tablets therapy should be observed for these signs or symptoms of fluid or electrolyte imbalance (hyponatremia, hypochloremic alkalosis, hypokalemia, hypomagnesemia or hypocalcemia): dryness of mouth, thirst, weakness, lethargy, drowsiness, restlessness, muscle pains or cramps, muscular fatigue, hypotension, oliguria, tachycardia, arrhythmia, or gastrointestinal disturbances such as nausea and vomiting. The postural hypotension that sometimes occurs can usually be managed by getting up slowly.
Hypotension is a potential side effect of Furosemide tablets, and it can be managed by getting up slowly. Patients receiving Furosemide tablets therapy should be observed for signs or symptoms of fluid or electrolyte imbalance, including hypotension.
- Key points:
From the Research
Hypotension and Lasix Limitation
- Hypotension, or low blood pressure, can be managed with various medications, including midodrine, which has been shown to be effective in increasing standing blood pressure and improving symptoms of orthostatic hypotension 3, 4.
- Lasix, also known as furosemide, is a loop diuretic that can be used to treat heart failure and edema, but its use can be limited by its potential to cause hypotension and other side effects 5, 6.
- The management of orthostatic hypotension involves a combination of nonpharmacologic and pharmacologic measures, including the use of midodrine, fludrocortisone, and other medications 7.
- The choice of diuretic, including Lasix, depends on the individual patient's clinical situation and the presence of other co-morbidities 5.
- Loop diuretics, including Lasix, have been shown to have a modest blood pressure lowering effect, but their use can be limited by their potential to cause adverse effects, including hypotension and electrolyte imbalances 6.
Treatment Options
- Midodrine is a prodrug that is converted to its active form, desglymidodrine, which is a selective alpha 1-adrenoceptor agonist that can increase standing blood pressure and improve symptoms of orthostatic hypotension 3, 4.
- Fludrocortisone is a mineralocorticoid that can be used to treat orthostatic hypotension, but its use can be limited by its potential to cause adverse effects, including renal and cardiac failure 7.
- Lasix, or furosemide, is a loop diuretic that can be used to treat heart failure and edema, but its use can be limited by its potential to cause hypotension and other side effects 5, 6.
Adverse Effects
- Midodrine can cause adverse effects, including piloerection, pruritus, and urinary retention, but these effects are generally mild and can be controlled by reducing the dosage 3, 4.
- Lasix, or furosemide, can cause adverse effects, including hypotension, electrolyte imbalances, and renal failure, which can limit its use in certain patients 5, 6.
- The risk of supine hypertension, which is associated with midodrine therapy, can be reduced by taking the final daily dose at least 4 hours before bedtime 3.