Lasix

Lasix (furosemide) is a loop diuretic. It suppresses the absorption of chlorine and sodium ions in the ascending part of the Henle loop, distal and proximal tubules of the nephron.

Pharmacology

Lasix disrupts the reabsorption of sodium ions, chlorine in the thick segment of the ascending part of the Henle loop. Due to the increase in the release of sodium ions, a secondary (indirectly osmotically bound by water) enhanced excretion of water and increased secretion of potassium ions in the distal part of the renal tubule occur. At the same time, the excretion of calcium and magnesium ions increases.

Lasix has secondary effects due to the release of intrarenal mediators and the redistribution of intrarenal blood flow. There is no attenuation of the effect against the background of course treatment.

Indications

• Edema syndrome in chronic congestive heart failure (if treatment with diuretics is required);
• Edema syndrome in acute congestive heart failure;
• Edema syndrome in chronic renal failure;
• Maintaining fluid secretion in acute renal failure, including during pregnancy and childbirth;
• Edema caused by nephrotic syndrome (if treatment with diuretics is required);
• Edematous syndrome in liver diseases (if additional treatment with aldosterone antagonists is necessary);
• Arterial hypertension;
• Hypertensive crisis (as maintenance therapy);
• Maintenance of forced diuresis.

Contraindications

• Hypersensitivity to the active substance and to any of the excipients of the drug;
• Allergy to sulfonamides (sulfonamide antimicrobials or drugs derived from sulfonylureas);
• Renal failure with anuria (in the absence of a reaction to taking furosemide);
• Hepatic coma and precoma associated with hepatic encephalopathy;
• Severe hypokalemia;
• Severe hyponatremia;
• Hypovolemia (with or without a decrease in blood pressure) or dehydration;
• Pronounced violations of the outflow of urine of any etiology, including unilateral damage to the urinary tract;
• Cardiac glycoside intoxication;
• Acute glomerulonephritis;
• Decompensated aortic and mitral stenosis, hypertrophic obstructive cardiomyopathy;
• Increased central venous pressure (over 10 mmHg);
• Children’s age up to 3 years;
• Pregnancy;
• The period of breastfeeding.

With caution:

• Arterial hypotension;
• Conditions where an excessive decrease in blood pressure is especially dangerous (severe stenosis of the coronary and / or cerebral arteries);
• Acute myocardial infarction (increased risk of cardiogenic shock);
• Latent or manifest diabetes mellitus;
• Gout;
• Hepatorenal syndrome;
• Hypoproteinemia (for example, nephrotic syndrome, when it is possible to reduce the diuretic effect and increase the risk of developing the ototoxic effect of furosemide);
• Partial obstruction of the urinary tract (prostatic hyperplasia, narrowing of the urethra);
• An increased risk of developing disorders of the water-electrolyte balance and acid-base state
• Significant loss of fluid (vomiting, diarrhea, excessive sweating, monitoring of the state of water-electrolyte balance and acid-base state);
• Pancreatitis;
• Ventricular cardiac arrhythmias in the anamnesis;
• Systemic lupus erythematosus;
• The simultaneous use of risperidone in elderly patients with dementia (risk of increased mortality).

Pregnancy and breastfeeding

Currently, there is insufficient clinical data to assess the potential teratogenic effects of Lasix when taken during pregnancy. The use of Lasix by pregnant women should be avoided and the drug should never be prescribed to treat physiological edema during pregnancy. Diuretics can cause placental ischemia with a risk of fetal malnutrition. Careful monitoring of fetal growth is required. Furosemide can be excreted in breast milk and inhibit lactation, therefore, if it necessary to use the drug during lactation, breastfeeding should be stopped.

Dosage and administration

The selection of the dose is carried out taking into account the severity of the edematous syndrome and the clinical picture of the disease. During therapy, it is possible to adjust the dosage regimen taking into account the severity of the diuretic response and positive dynamics during the course of the disease.
The drug must be taken before meals. Adults receive 20 mg or 40 mg of furosemide per day, divided into two or three doses. The interval between tablets should be at least 6 hours. With low treatment effectiveness, it is possible to increase the daily dose to 160 mg. After eliminating the violations, the drug is taken in minimally effective doses every other day or every two days. If you have to take Lasix with other antihypertensive drugs, their dose is halved.

Side effects

• Cardiovascular system: decrease in blood pressure, orthostatic hypotension, collapse, tachycardia, arrhythmias, decrease in BCC;
• Central nervous system and peripheral nervous system: dizziness, headache, myasthenia gravis, cramps (tetany), paresthesia, apathy, adynamia, weakness, lethargy, drowsiness, confusion;
• Senses: impaired vision and hearing;
• Digestive system: decreased appetite, dry mouth, thirst, nausea, vomiting, constipation or diarrhea, cholestatic jaundice, pancreatitis (exacerbation);
• Genitourinary system: oliguria, acute urinary retention (in patients with prostatic hypertrophy), interstitial nephritis, hematuria, decreased potency;
• Hematopoietic system: leukopenia, thrombocytopenia, agranulocytosis, aplastic anemia;
• Water-electrolyte metabolism: hypokalemia, hyponatremia, hypochloraemia, hypocalcemia, hypomagnesemia, metabolic alkalosis;
• Metabolism: hypovolemia, hypokalemia, hyponatremia, hypochloremia, hypokalemic metabolic alkalosis (as a result of these disorders – arterial hypotension, dizziness, dry mouth, thirst, arrhythmia, muscle weakness, cramps), hyperuricemia (with possible exacerbation of gout), hyperglycemia;
• Allergic reactions: purpuritis, urticaria erythema multiforme, vasculitis, necrotizing angiitis, pruritus, chills, fever, photosensitivity, anaphylactic shock.

Drug interactions

Not recommended combinations:

• Chloral hydrate;
• Aminoglycosides.

Combinations to be used with caution:

• Ototoxic drugs;
• Cisplatin;
• Sucralfate;
• Angiotensin-converting enzyme (ACE) inhibitors;
• Angiotensin II receptor antagonists;
• Lithium salts;
• Risperidone;
• Levothyroxine.

Interactions to consider:

• Cardiac glycosides;
• Glucocorticosteroids, carbenoxolone, large quantities of licorice, and prolonged use of laxatives;
• Nephrotoxic drugs;
• Nonsteroidal anti-inflammatory drugs (NSAIDs);
• Salicylates;
• Phenytoin;
• Antihypertensives, diuretics or other drugs that can lower blood pressure;
• Probenecid, methotrexate, or other drugs;
• Hypoglycemic agents (both for oral administration and insulin preparations), pressor amines (epinephrine, norepinephrine);
• Theophylline, diazoxide, curariform muscle relaxants;
• High doses of some cephalosporins;
• Cyclosporin A;
• X-ray contrast agents.

Overdose

An overdose of Lasix can cause a decrease in blood pressure, collapse, shock, hypovolemia, dehydration, blood concentration, arrhythmias (including AV block, ventricular fibrillation), acute renal failure with anuria, thrombosis, thromboembolism, drowsiness, confusion, flaccid paralysis, apathy.
Treatment: correction of water-electrolyte balance and acid-base state, replenishment of circulating blood volume, gastric lavage, intake of activated charcoal, symptomatic treatment. There is no specific antidote.