1 tablet contains:
hydrochlorothiazide 25 mg;
Hypothiazide is a diuretic.
The primary mechanism of action of thiazide diuretics is to increase urine output by blocking the reabsorption of sodium and chlorine ions at the beginning of the renal tubules. By doing so, they increase the excretion of sodium and chlorine and therefore water. The excretion of other electrolytes, namely potassium and magnesium, is also increased.
At maximum therapeutic doses, the natriuretic / diuretic effect of all thiazides is approximately the same. Natriuresis and diuresis occur within 2 hours and reach their maximum after about 4 hours. They also decrease the activity of carbonic anhydrase by increasing the excretion of bicarbonate ion, but this effect is usually weak and does not affect urine pH. Hydrochlorothiazide also has antihypertensive properties. Thiazide diuretics have no effect on normal blood pressure.
Hydrochlorothiazide is incomplete, but rather rapidly absorbed from the gastrointestinal tract. This effect persists for 6-12 hours. After oral administration of a dose of 100 mg, Cmax in blood plasma is achieved after 1.5-2.5 hours.
At the maximum diuretic activity (approximately 4 hours after administration), the concentration of hydrochlorothiazide in the blood plasma is 2 μg / ml. Plasma protein binding is 40%. It is excreted mainly through the kidneys (filtration and secretion) in an unchanged form. T1 / 2 for patients with normal renal function is 6.4 hours, for patients with moderate renal insufficiency - 11.5 hours, and for patients with Cl creatinine less than 30 ml / min - 20.7 hours.
Hydrochlorothiazide crosses the placental barrier and is excreted in breast milk.
- arterial hypertension (used both in monotherapy and in combination with other antihypertensive drugs);
- edematous syndrome of various origins (chronic heart failure, nephrotic syndrome, premenstrual syndrome, acute glomerulonephritis, chronic renal failure, portal hypertension, corticosteroid treatment);
- control of polyuria, mainly in nephrogenic diabetes insipidus;
- prevention of the formation of stones in the genitourinary tract in predisposed patients (reduction of hypercalciuria).
Application during pregnancy and lactation
Hydrochlorothiazide crosses the placental barrier. The use of the drug in the first trimester of pregnancy is contraindicated. In the II and III trimesters of pregnancy, the drug can be prescribed only in case of urgent need, when the benefit to the mother outweighs the potential risk to the fetus and / or child. There is a risk of developing fetal or newborn jaundice, thrombocytopenia and other consequences.
The drug passes into breast milk; therefore, if the use of the drug is absolutely necessary, then breastfeeding should be discontinued.
- hypersensitivity to the drug or to other sulfonamides;
- severe renal (Cl creatinine - less than 30 ml / min) or liver failure;
- difficult to control diabetes mellitus;
- Addison's disease:
- refractory hypokalemia, hyponatremia, hypercalcemia;
- children under 3 years of age (solid dosage form).
Use with caution in hypokalemia, hyponatremia, hypercalcemia, in patients with coronary artery disease, with cirrhosis of the liver, gout, in the elderly, in patients suffering from lactose intolerance, while taking cardiac glycosides.
Hypokalemia, hypomagnesemia, hypercalcemia, and hypochloremic alkalosis: dry mouth, thirst, irregular heart rhythm, changes in mood or psyche, cramps and muscle pain, nausea, vomiting, unusual tiredness or weakness. Hypochloremic alkalosis can cause hepatic encephalopathy or hepatic coma.
Hyponatremia: confusion, convulsions, lethargy, slow thinking, fatigue, excitability, muscle cramps.
Metabolic phenomena: hyperglycemia, glucosuria, hyperuricemia with the development of a gout attack. Treatment with thiazides can reduce glucose tolerance, and latent diabetes mellitus may manifest. Serum lipid levels may increase with high doses.
From the gastrointestinal tract: cholecystitis or pancreatitis, cholestatic jaundice, diarrhea, sialadenitis, constipation, anorexia.
From the cardiovascular system: arrhythmias, orthostatic hypotension, vasculitis.
From the nervous system and sensory organs: dizziness, blurry vision (temporarily), headache, paresthesia.
From the side of hematopoiesis: very rarely - leukopenia, agranulocytosis, thrombocytopenia, hemolytic anemia, aplastic anemia.
Hypersensitivity reactions: urticaria, purpura, necrotizing vasculitis, Stevens-Johnson syndrome, respiratory distress syndrome (including pneumonitis and noncardiogenic pulmonary edema), photosensitivity, anaphylactic reactions up to shock.
Other phenomena: decreased potency, impaired renal function, interstitial nephritis.
The simultaneous use of the drug with lithium salts should be avoided (renal clearance of lithium decreases, its toxicity increases).
Use with caution with the following drugs:
- antihypertensive drugs (their effect is potentiated, it may be necessary to adjust the dose);
- cardiac glycosides (hypokalemia and hypomagnesemia, associated with the action of thiazide diuretics, can increase the toxicity of digitalis);
- amiodarone (its use simultaneously with thiazide diuretics may lead to an increased risk of arrhythmias associated with hypokalemia);
- hypoglycemic agents for oral administration (their effectiveness decreases, hyperglycemia may develop);
- corticosteroid drugs, calcitonin (increase the degree of potassium excretion);
- NSAIDs (can weaken the diuretic and hypotensive effect of thiazides);
- non-depolarizing muscle relaxants (their effect may be enhanced);
- amantadine (clearance of amantadine can be reduced by hydrochlorothiazide, which leads to an increase in the concentration of amantadine in plasma and possible toxicity);
- cholestyramine, which reduces the absorption of hydrochlorothiazide;
- ethanol, barbiturates and narcotic analgesics, which enhance the effect of orthostatic hypotension.
The effect of the drug on laboratory test data
Thiazides can reduce plasma levels of iodine bound to proteins.
Thiazides should be discontinued before testing the function of the parathyroid glands. The serum bilirubin concentration may be increased.
How to take, course of administration and dosage
Inside, after eating.
The dosage should be selected individually. With constant medical supervision, the minimum effective dose is established.
Due to the increased loss of potassium and magnesium ions during treatment (the serum potassium level may decrease below 3.0 mmol / l), it becomes necessary to replace potassium and magnesium.
Adults. As an antihypertensive agent, the usual starting daily dose is 25–50 mg once, as monotherapy or in combination with other antihypertensive agents. For some patients, an initial dose of 12.5 mg is sufficient, both as monotherapy and in combination. It is necessary to use the minimum effective dose not exceeding 100 mg / day. If Hypothiazid® is combined with other antihypertensive drugs, it may be necessary to reduce the dose of another drug in order to prevent an excessive decrease in blood pressure.
The antihypertensive effect appears within 3-4 days, but it may take up to 3-4 weeks to achieve the optimal effect. After the end of treatment, the hypotensive effect persists for 1 week.
Edematous syndrome of various origins. The usual starting dose for the treatment of edema is 25–100 mg of the drug once a day or once every 2 days. Depending on the clinical response, the dose may be reduced to 25-50 mg once a day or once every 2 days. In some severe cases, doses up to 200 mg / day may be required at the beginning of treatment.
In premenstrual syndrome, the usual dose is 25 mg / day and is used from the onset of symptoms to the onset of menstruation.
In nephrogenic diabetes insipidus, a usual daily dose of 50–150 mg (in divided doses) is recommended.
Children. Doses should be adjusted based on the weight of the child. The usual pediatric daily doses are 1–2 mg / kg or 30–60 mg / m2 of body surface, given once daily. The total daily dose for children aged 3 to 12 years is 37.5-100 mg.
The most prominent manifestation of a hydrochlorothiazide overdose is acute fluid and electrolyte loss, resulting in the following signs and symptoms:
Cardiovascular: tachycardia, decreased blood pressure, shock.
Neuromuscular: weakness, confusion, dizziness and spasms of the calf muscles, paresthesia, impaired consciousness, fatigue.
Gastrointestinal: nausea, vomiting, thirst.
Renal: polyuria, oliguria, or anuria (due to hemoconcentration).
Laboratory indicators: hypokalemia, hyponatremia, hypochloremia, alkalosis, increased blood urea nitrogen (especially in patients with renal failure).
Treatment: there is no specific antidote for hydrochlorothiazide overdose.
Induction of vomiting, gastric lavage can be methods of drug elimination.
The absorption of the drug can be reduced by the appointment of activated carbon. In the case of a decrease in blood pressure or shock, the BCC and electrolytes (potassium, sodium) should be replaced.
Water-electrolyte balance (especially serum potassium) and renal function should be monitored until normal values are established.
With long-term course treatment, it is necessary to carefully monitor the clinical symptoms of imbalance in the water-electrolyte balance, primarily in high-risk patients: patients with diseases of the cardiovascular system and impaired liver function; in case of severe vomiting or when there are signs of imbalance in water and electrolyte balance such as dry mouth, thirst, weakness, lethargy, drowsiness, anxiety, muscle pain or cramps, muscle weakness, hypotension, oliguria, tachycardia, gastrointestinal complaints.
Hypokalemia can be avoided by using potassium-containing drugs or foods rich in potassium (fruits, vegetables), especially in the case of increased potassium loss (increased diuresis, prolonged treatment) or concomitant treatment with digitalis glycosides or corticosteroid drugs.
It has been shown that thiazides increase the excretion of magnesium in the urine; this can lead to hypomagnesemia.
With reduced renal function, creatinine clearance must be monitored. In patients with impaired renal function, the drug can cause azotemia, and cumulative effects can also develop. If impaired renal function is evident, discontinuation of the drug should be considered when oliguria occurs.
Thiazides are prescribed with caution in patients with impaired liver function or with progressive liver diseases, since a small change in the water-electrolyte balance, as well as in the level of ammonium in the serum, can cause hepatic coma.
In the case of severe cerebral and coronary sclerosis, the administration of the drug requires special care.
Treatment with thiazide drugs may interfere with glucose tolerance. During a long course of treatment with overt and latent diabetes mellitus, systematic monitoring of carbohydrate metabolism is necessary; it may be necessary to change the dose of hypoglycemic drugs. Increased monitoring of patients with impaired uric acid metabolism is required.
Alcohol, barbiturates, narcotic analgesics increase the orthostatic hypotensive effect of thiazide diuretics.
With prolonged therapy, in rare cases, a pathological change in the parathyroid glands was observed, accompanied by hypercalcemia and hypophosphatemia. Thiazides can reduce the amount of iodine that binds to serum proteins without showing signs of thyroid dysfunction.
In patients suffering from lactose intolerance, gastrointestinal complaints may occur due to the presence of lactose in the tablets: Hypothiazid® 25 mg tablets contain 63 mg of lactose, Hypothiazid® 100 mg - 39 mg of lactose.
Impact on the ability to drive and perform work requiring increased attention. At the initial stage of using the drug (the duration of this period is determined individually), it is forbidden to drive a car and perform work that requires increased attention.