SPIRONOLACTONE GNR 75 mgSpironolactone in the form of 50 mg scored tablets.Action
Diuretic (drug that increases renal filtration) hyperkalemic (causes an increase in the level of potassium in the blood). It is also called a potassium-sparing diuretic, which modifies the exchanges between sodium and potassium in a specific area of the kidney: the distal convoluted tubule. Its action is through an antialdosterone effect.
Aldosterone is one of the hormones called mineralocorticosteroids. It is secreted in the cortex (i.e., the peripheral part) of the adrenal glands (glands located on the kidneys) and allows the kidneys to reabsorb sodium and eliminate potassium. These two metals play a key role in regulating the body's blood pressure.
The main role of aldosterone is its action on the nephron (the kidney's functioning unit). In the nephron, there is an area called the distal tubule where aldosterone acts by removing sodium from the primary urine (the first urine produced by the nephron) into the blood. Conversely, aldosterone allows potassium to pass into the urine. Sodium retained in the blood will cause water retention, which results in an increase in blood volume, and therefore an increase in blood pressure.
In cases of significant water loss (such as diarrhea or repeated vomiting), the body increases aldosterone production to preserve its sodium. The adrenal glands then secrete more aldosterone.
Conversely, when there is too much sodium in the body, the adrenal glands produce less aldosterone, causing sodium to leak into the urine.
The regulation of this entire system involves substances grouped under the term renin-angiotensin system.
Indications
· Increased blood pressure
· Edema of cardiac and hepatic origin: water and salt retention of renal origin or secondary to nephrotic syndrome (set of symptoms that accompany glomerulonephritis, or kidney disease characterized by damage to the glomeruli).
· Primary hyperaldosteronism. Hyperaldosteronism (excessive secretion of aldosterone) results in hypokalemia (drop in blood potassium levels). This hyperaldosteronism is either primary (benign tumor of the adrenal gland) or secondary to a decrease in blood volume in the body.
· In case of myasthenia, spironolactone is used as adjuvant therapy
Dosage
In tablet form, in adults and in cases of edema: 50 to 100 mg, and up to 300 mg per day at the start of treatment, adapted thereafter.
In case of idiopathic cyclic edema: 50 to 100 mg per day as maintenance treatment
In the presence of high blood pressure: 50 to 100 mg per day (combined with other antihypertensives)
In the presence of hyperaldosteronism: up to 300 mg per day, and in children 2 mg per kilo per day.
Contraindications
· Hyperkalemia (increased potassium levels, greater than 5,5 mmol per liter)
· Severe acute renal failure
· In terminal liver failure, spironolactone should not be used
· Some patients have hypersensitivity or allergy to this molecule.
Drugs interactions
Contraindicated:
· Potassium, outside of a hypokalemic episode
· Other hyperkalemic diuretics (which increase the level of potassium in the blood)
Not recommended:
· Angiotensin converting enzyme inhibitors
· Lithium
To watch out for:
· Non-steroidal anti-inflammatory drugs (not containing cortisone)
· Metformin
· Iodinated contrast products used for certain radiological examinations (scanner, X-ray with preparation, etc.)
· Hypokalemic diuretics, i.e. those that cause a decrease in the level of potassium in the blood
Adverse reactions
· Gynecomastia (increase in the volume of the mammary glands) generally reversible when treatment is stopped
· Impotence in men
· Menstrual disorders
· Gastrointestinal disorders
· Drowsiness
· A skin rash
· Headaches
· A risk of hyperkalemia (excessive elevation of the potassium level in the blood) in patients with cirrhosis when the natremia (sodium level in the blood) is less than 130 mmol per liter
Pregnancy and breast feeding
The administration of this molecule is not recommended during pregnancy and breastfeeding.