tiazidici

Tiazidici, known in English as thiazide diuretics, are a class of medications principally used to treat hypertension and edema. They are sulfonamide derivatives that act by inhibiting the Na-Cl cotransporter in the distal convoluted tubule of the kidney. This inhibition reduces reabsorption of sodium and chloride, promoting natriuresis and a mild diuretic effect. Thiazides also increase calcium reabsorption in the distal tubule, which can help reduce the risk of certain types of kidney stones.

Common agents in this class include hydrochlorothiazide, chlorthalidone, indapamide, and metolazone. Thiazide-like diuretics such as chlorthalidone and indapamide share the same basic mechanism but may differ in potency, duration of action, and clinical indications. They are often chosen for sustained blood pressure control and for edema associated with heart failure, cirrhosis, or nephrotic syndrome. Thiazides can also be used in nephrogenic diabetes insipidus to reduce polyuria.

Adverse effects commonly relate to electrolyte and fluid balance. Notable risks include hypokalemia, hyponatremia, hyperglycemia or glucose intolerance, dehydration, and photosensitivity. They may raise serum urate and can precipitate gout in susceptible individuals. NSAIDs can reduce the antihypertensive effect of thiazides, and their use requires caution in patients with kidney disease or severe renal impairment.

Contraindications include anuria and significant hypersensitivity to sulfonamides. As with all diuretics, therapy should be individualized, monitoring electrolytes, kidney function, and blood pressure.