Furosemide (furosemide) is an organic chemical compound from the group of sulfonamides, belonging to the group of loop diuretics (it works in the area of the nephron loop - the so-called Henle loop, hence the name of the group). How does furosemide work? What are the indications and contraindications for the administration of furosemide? What interactions may occur with furosemide?
Furosemideis a substance whose function is to inhibit the reabsorption of chloride and sodium ions. Thanks to this, the excretion of these elements with urine is intensified, and thus - the volume of water excreted increases.
Furosemide: indications for use
The action of furosemide is used in the treatment of diseases such as:
- nephrotic syndrome
- cirrhosis of the liver
- acute and chronic renal failure
- thiazide-resistant hypertension
- severe heart failure
- hypercalcemia
It is also used in attempts to prevent and reduce the effects of cerebral edema.
Furosemide is given to children and adults in the case of edema caused by congestive heart failure, kidney disease and cirrhosis of the liver. In adults, this drug is also administered, in combination with other drugs, in the case of hypertension.
In addition, it can be used to increase the elimination of drugs by the kidneys in the event of intoxication of the body.
In medicine, it is also used (including adequate hydration) in the case of hypernatremia or hypercalcemia.
The onset of the diuretic effect of furosemide occurs approximately 0.5-1 hour after oral ingestion and usually lasts for 6-8 hours.
The antihypertensive effect, unfortunately, appears only after a few days of regular use.
When should you not use furosemide?
Furosemide should not be used in the presence of diseases such as:
- anuria or renal failure with anuria
- hypovolemia or dehydration
- severe hyponatraemia
- severe hypokalemia
- Pre-coma or coma associated with hepatic encephalopathy
It cannot be used in breastfeeding womenbreastfeeding or pregnant, unless the doctor deems it necessary (but in this case, it is usually a short-term treatment under strict control).
In each of these situations, it is the doctor who, after performing tests and an interview, taking into account the risks and potential benefits, decides to include furosemide in the therapy.
Furosemide: side effects
Furosemide is one of the loop diuretics, which can cause electrolyte disturbances: deficiencies of magnesium, sodium, potassium, chlorine and calcium.
Furosemide taken in too high doses may cause dehydration.
Drug taken without medical advice may cause orthostatic hypotension and collapse.
In addition, the preparation may cause:
- weakness
- temporary hearing impairment
- vomiting
- nausea
- dizziness when changing body position
- increase in uric acid concentration and increase gout
- transient increases in blood creatinine, glucose and cholesterol
- headache
When to exercise extreme caution when using furosemide?
Some diseases may be a contraindication to the use of this substance or an indication to change the dosage due to possible interactions and side effects, for example :
- before the patient starts treatment with furosemide, the doctor recommends constant monitoring of electrolytes in the blood and blood pressure
- patients with impaired urination or prostatic hyperplasia may have an increased risk of acute urinary retention
- if there is cirrhosis of the liver, treatment with furosemide should be initiated in a hospital, under strict medical supervision
- furosemide can cause dry damage, especially tinnitus; these damages may be temporary or permanent
- the use of furosemide in patients with cirrhosis of the liver who are taking concurrent systemic corticosteroids or corticotropin (ACTH) may cause or worsen already existing hypokalemia
- in people allergic to sulfonamides, the preparation may cause skin changes, for example
- in people with diabetes, furosemide may increase blood glucose levels
Furosemide: interactions
Furosemide can cause sudden drops in blood pressure in people who take antihypertensive drugs or other preparations that, although used for a different purpose, can also lower blood pressure. These are, among others MAO monoamine oxidase inhibitors, certain antidepressants, sedatives, medicationshypnotics, neuroleptics, barbiturates, opioids). Such pressure surges can be dangerous to he alth and life.
The preparation may reduce the effectiveness of oral antidiabetic drugs and insulin. You may need to change its dosage.
The drug increases the toxic effect of aminoglycoside antibiotics (especially neomycin and vancomycin) and the nephrotoxic effect of cephalosporins (especially cephalexin).
The use of furosemide in parallel with lithium s alts is not recommended. If necessary - the doctor reduces the doses of both preparations.
This substance may affect the action of muscle relaxants used in parallel, as well as increase the toxicity and potency of salicylates.
Diuretics should be taken with caution with non-steroidal anti-inflammatory drugs. NSAIDs may reduce the antihypertensive properties of diuretics. This can lead to a risk of kidney damage and kidney problems. Especially if the person also suffers from kidney failure.
Parallel use of the preparation with angiotensin converting enzyme (ACE) inhibitors causes the risk of hypotension. Therefore, your doctor may recommend that you reduce the doses or discontinue diuretics 2-3 days before starting treatment with ACE inhibitors.
The levels of electrolytes (especially potassium, calcium and magnesium), creatinine, urea, and acid-base parameters should be monitored frequently during treatment, and blood and urine glucose levels in diabetic patients should be monitored.
Furosemide can also cause:
- blurred vision
- dizziness
- sleepiness
Furosemide: overdose
Symptoms of furosemide overdose are related to the diuretic effect. These include:
- metabolic alkalosis
- dehydration
- hypotension
- hypokalemia
- electrolyte imbalance
- reduction of circulating blood volume
Treatment is based on hydration which increases the blood volume in the body and replenishes the electrolyte deficiency.
Hemodialysis unfortunately does not accelerate the excretion of furosemide from the body.
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- Diuretics or diuretics