Torasemide - instructions for use, dose, side effects, contraindications

The main mechanism of action is due to the reversible binding of torasemide to the sodium / chlorine / potassium transporter located in the apical membrane of the thick segment of the ascending loop of Henle, as a result of this, the reabsorption of sodium ions decreases and completely inhibits and the osmotic pressure of the intracellular fluid decreases and the water reabsorption decreases.

Torasemide is less than furosemide, causes hypokalemia, while it shows great activity and its effect is more prolonged.

Diuretic effect develops about an hour after ingestion, reaching a maximum after 3-6 hours, and lasts from 8 to 10 hours. "Loopback" diuretic.

Pharmacokinetics:

Absorption is fast. F - 80%. The connection with plasma proteins is 97-99% and higher.VD 0,14-0,19 l / kg, increases with hypoalbuminemia. Biotransformation in the liver (isoenzyme CYP2C9) with the formation of 5 metabolites, 3 of which are active (torasemide - 80% of the activity, M1 - 9%, M3 - 11%). The half-life period is 2.2-3.8 hours, does not change with moderate damage to kidney function, with CRF, the M1 metabolite accumulates. Elimination by the kidneys - 24% unchanged. It is poorly removed during hemodialysis.

Indications:

Edema syndrome of various genesis, including chronic heart failure, liver and kidney diseases; arterial hypertension.

ICD-10

IX.I10-I15.I10 Essential [primary] hypertension

IX.I30-I52.I50.0 Congestive heart failure

XVIII.R50-R69.R60 Edema, not elsewhere classified

Contraindications:

Hypersensitivity (including sulfonamides), anuria, hepatic coma and precoma, CRF with increasing azotemia, arterial hypotension, arrhythmia; pregnancy, breast-feeding; age to 18 years (efficacy and safety not established).

Carefully:

Predisposition to hyperuricemia, gout; diabetes mellitus (including latent).

Pregnancy and lactation:

Studies in humans have not been conducted.Routine use of diuretics during a normal pregnancy is not recommended because of potential risks to the mother and fetus. However, diuretics can be taken if they are needed to treat hypertension that existed before pregnancy. Diuretics do not prevent the development of toxemia in pregnancy, and their effectiveness in toxemia has not been proven. Diuretics are indicated for the treatment of edema and in the form of short courses for patients with severe hypervolemia. There is no information on the penetration into breast milk.

Recommendations for FDA - Category B.

Dosing and Administration:

Accepted inside. Depending on the indications, the dose is 5-20 mg 1 time / day.

A single dose of more than 40 mg is not recommended, since its effect has not been studied. Apply long or until the disappearance of swelling.

Side effects:

From the side metabolism: infrequently - hypercholesterolemia, hypertriglyceridemia, polydipsia.

From the side nervous system: often - dizziness, headache, drowsiness; infrequently - cramps of the muscles of the lower limbs; frequency is unknown - confusion, fainting, paresthesia in the extremities.

From the side of cardio-vascular system: infrequently - an extrasystole, a tachycardia, the strengthened palpitation, a reddening of the face; frequency is not known - excessive arterial hypotension, deep vein thrombosis, thromboembolism, hypovolemia.

From the side respiratory system: infrequently - nosebleeds.

From the side digestive system: often - diarrhea; infrequently - abdominal pain, flatulence; frequency unknown - nausea, vomiting, loss of appetite, pancreatitis, dyspepsia.

From the side kidney and urinary tract: often - increased frequency of urination, polyuria, nocturia; infrequent - frequent urge to urinate; frequency unknown - urinary retention (in patients with urinary tract obstruction), increased urea and creatinine concentrations in the blood.

Laboratory indicators: infrequently - an increase in the number of platelets; frequency is unknown - hyperglycemia, hyperuricemia, hypokalemia, a decrease in the number of erythrocytes, leukocytes and platelets, a slight increase in the activity of the alkaline phosphatase in the blood, an increase in the activity of certain hepatic enzymes (eg GGT), hyponatremia, hypochloraemia, metabolic alkalosis.

From the side sense organs: frequency unknown - visual impairment, ringing in the ears and hearing loss (usually, reversible).

From the side skin integument: frequency unknown - itching, rash, photosensitivity.

Other: infrequently - asthenia, weakness, thirst, hyperactivity, nervousness, increased fatigue.

Overdose:

Treatment is symptomatic.

Interaction:

Torasemide increases the toxicity of cardiac glycosides.

With simultaneous administration with mineral- and glucocorticoids, laxatives, an increase in the excretion of potassium is possible.

Torasemide enhances the effect of antihypertensive drugs.

Torasemide, especially in high doses, can enhance the nephrotoxic and ototoxic effect of aminoglycosides, antibiotics, platinum preparations, cephalosporins.

Torasemide can enhance the action of curare-like muscle relaxants and theophylline.

With the simultaneous use of salicylates in high doses, it is possible to intensify their toxic effects.

Torasemide weakens the effect of hypoglycemic drugs.

Sequential or simultaneous administration of torasemide with ACE inhibitors can lead to a short-term drop in blood pressure.This can be avoided by decreasing the initial dose of an ACE inhibitor or by lowering the dose of torasemide (or temporarily abolishing it).

NSAIDs and probenecid can reduce the diuretic and hypotensive effect of torasemide.

Bioavailability and, as a consequence, the effectiveness of torasemide can be reduced by joint therapy with colestyramine.

Torasemide may increase the toxicity of lithium preparations and the ethoxyrinic acid's ototoxicity.

Special instructions:

3 times more active than furosemide.

With CHF II-IV, FC (NYHA) improves the quality of life to a greater extent than furosemide.

20 mg / day torasemide is more effective than 40 mg / day furosemide in reducing body weight in CHF and in reducing the severity of symptoms.

Instructions

Torasemide (Torasemidum)