The active substance – furosemide – has a diuretic effect due to the blockade of the reverse absorption of sodium and chlorine ions in the ascending part of the loop of Henle. To an insignificant degree, Lasix also acts on convoluted tubules, this mechanism is not associated with antialdosterone activity or inhibition of carbonic anhydrase. Lasix promotes the excretion of potassium, magnesium, calcium.
With intravenous injection, Lasix is able to quickly reduce arterial pressure, pulmonary artery pressure, preload and pressure in the left ventricle. Diuretic effect is observed after 5 minutes, reaching a maximum within half an hour, the duration of the diuretic period is about 2 hours.
When administered, the diuretic effect of Lasix begins within the first hour, reaching a maximum after 1.5-2 hours, the duration of the effective period is about 7 hours.
In the body, Lasix is metabolized and excreted, mainly with urine, in the form of a compound with glucuronic acid.
Mode of application
The method of application and dosage regimen should be set individually, depending on the degree of disturbance of the water-electrolyte balance, the magnitude of glomerular filtration. In the future, dose adjustment is necessary, depending on the degree of severity of the patient’s condition, the magnitude of diuresis. Usually, the drug is given in the form of tablets, but if this is not possible, or it is an urgent condition, the drug is injected intravenously, the time of Lasix administration should not be less than 1.5-2 minutes.
At an average degree of edematous syndrome, the initial dose of Lasix is 20-80 mg orally or 20-40 mg intramuscularly or intravenously, with insufficient effect, the dose can be increased by 40 mg in case of oral intake and by 20 mg if Lazix is injected . The dose increase is possible not earlier than 6-8 hours after taking the initial oral dose and not earlier than 2 hours after parenteral administration. Correction of the dose occurs before the appearance of an adequate diuresis. The so-called single dose can be administered once or twice a day. The maximum effect of Lasix is observed if the drug is prescribed 2-4 times a week.
When using Lasix in large doses, there is a decrease in BCC (the volume of circulating blood), resulting in a thickening of the blood and possible thrombosis. A frequent side effect is the development of water-electrolyte disorders: alkalosis (including increased metabolic alkalosis in diabetes mellitus), sodium, chlorine, calcium, and potassium deficiency; Violation of biochemical properties of blood: increased levels of creatinine, cholesterol, triglycerides, uric acid (with exacerbation of gout), glucose (especially in diabetes mellitus).
Allergic reactions are possible, ranging from skin manifestations (purpura, dermatitis, pruritus, erythema) and up to anaphylactic shock.
Rarely there are violations from the blood: leukopenia, eosinophilia, hemolytic changes, agranulocytosis, thrombocytopenia.
In low-dose or premature babies, the use of Lasix in the first weeks of life can lead to an uncontrolled Botallov duct.