Products
Torasemide is commercially available in tablet form (Torem, generic). It has been approved in many countries since 1993.
Structure and properties
Torasemide (C16H20N4O3S, Mr = 348.4 g/mol) exists as a white powder that is practically insoluble in water. It is a pyridine-sulfonylurea derivative. Torasemide differs structurally from its precursor furosemide (Lasix, generics), a sulfonamide.
Effects
Torasemide (ATC C03CA04) has diuretic, antihypertensive, and antiedematous properties. The effects are due to inhibition of Na+/K+/2Cl–-Cotransporter at the ascending thick branch of the loop of Henle in the nephron of the kidney. This results in increased urinary excretion of sodium, potassium, chloride, and water. Torasemide exerts its effects from the lumen of the renal tubules. It has a duration of action of up to twelve hours. Torasemide has a longer half-life and higher bioavailability than furosemide.
Indications
- Hypertension
- Edema due to heart failure
- Ascites (abdominal dropsy), in combination with spironolactone.
- Edema in nephrotic syndrome.
- High doses: severe renal insufficiency, nephrotic syndrome with severely impaired renal function.
Dosage
According to the professional information. The tablets are usually taken once a day in the morning and independently of meals. Do not take before bedtime because sleep may be disturbed by increased urine output. If therapy is prolonged, laboratory values must be monitored.
Abuse
Torasemide may be abused as a masking agent and is prohibited during and outside of athletic competition.
Contraindications
- Hypersensitivity, including to sulfonylureas.
- Hypotension
- Renal failure with anuria
- Severe hepatic dysfunction with clouding of consciousness.
- Pregnancy, lactation
- Hypovolemia, hyponatremia, hypokalemia.
- Significant micturition disorders
For complete precautions, see the drug label.
Interactions
Torasemide has a high potential for interaction. Drug-drug interactions are possible with, for example, antihypertensives, antidiabetics, NSAIDs, and cardiac glycosides.
Adverse side effects
The most common possible adverse effects include gastrointestinal discomfort, headache, dizziness, and fatigue. Torasemide may cause metabolic side effects such as hyperuricemia, hyperglycemia, and hyperlipidemia, as well as disturbances in water and electrolyte balance (including low potassium, sodium, chloride, magnesium, and calcium levels).
