Substances which increase urine and solute production by the KIDNEYS. They are used in the treatment of heart failure, HYPERTENSION, and sometimes for ASCITES secondary to liver failure. They may work by extra-renal or renal mechanisms.
The potential side-effects of diuretics are HYPOKALAEMIA, DEHYDRATION, and GOUT (in susceptible individuals).
Renal mechanisms (a) Osmotic diuretics act by ‘holding’ water in the renal tubules and preventing its reabsorption (e.g. mannitol); (b) loop diuretics prevent sodium, and therefore water, reabsorption (e.g. FRUSEMIDE); (c) drugs acting on the cortical segment of the Loop of Henle prevent sodium reabsorption, but are ‘weaker’ than loop diuretics (e.g. THIAZIDES); (d) drugs acting on the distal tubule prevent sodium reabsorption by retaining potassium
Drugs used in pulmonary oedema (excess ?uid in the lungs) caused by failure of the left VENTRICLE of the HEART. DIURETICS cause an increase in excretion of URINE, thus reducing the amount of ?uid in the body. Intravenous administration of loop diuretics relieves patients’ breathlessness. They work by inhibiting resorption of ?uid in the renal tubule loops of the KIDNEYS. Frusemide and bumetanide are commonly used loop diuretic drugs that act quickly and last for six hours so that they can be given twice in 24 hours without disturbing the patient’s sleep.... loop diuretics
Drugs that help remove excess water from the body by increasing the amount lost as urine. They are used in the treatment of various disorders, which include severe premenstrual syndrome, hypertension, heart failure, the eye condition glaucoma, nephrotic syndrome, and cirrhosis of the liver.
Types of diuretic drug differ markedly in their speed and mode of action. Thiazide diuretics cause a moderate increase in urine production. Loop diuretics are fast-acting, powerful drugs. They are often used as an emergency treatment for heart failure. Potassium-sparing diuretics are used along with thiazide and loop diuretics, both of which may cause the body to lose too much potassium. Carbonic anhydrase inhibitors block the action of the enzyme carbonic anhydrase, which affects the amount of bicarbonate ions in the blood; these drugs increase urine output moderately but are effective only for short periods of time. Osmotic diuretics are used to maintain urine output following serious injury or major surgery.
Diuretic drugs may cause chemical imbalances in the blood.
Hypokalaemia (low blood levels of potassium) is usually treated with potassium supplements or potassium-sparing diuretic drugs.
A diet rich in potassium may be helpful.
Some diuretics raise the blood level of uric acid, increasing the risk of gout.
Certain diuretics increase the blood glucose level, which can cause or worsen diabetes mellitus.... diuretic drugs
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