DIURETICS



DIURETICS

 

THIAZIDES - Bendoflumethiazide (Bendrofluazide) *****

 

• Reduce Na reabsorbtion in the distal tubule*. Also increase K loss

• Increased Mg loss but decreased Ca loss

• Induce hyperglycaemia and may exacerbate pre-existing diabetes mellitus

• Produce anti-hypertensive effect which is not secondary to diuresis but probably due to vasodilation

LOOP DIURETICS - Furosemide (Frusemide), Bumetanide *****

• Rapid onset and short duration of action, cause marked diuresis

• Protein-bound

• Site of action - ascending limb of the loop of Henle *

• Cause loss of Na, Cl as well as K, Ca and Mg

POTASSIUM-SPARING DIURETICS*****

Amiloride, Triamterene, Spironolactone 

• Amiloride & triamterene* - decreases K secretion in the collecting ducts

• Spironolactone *- aldosterone antagonist - inhibits Na reabsorbtion and K secretion in the distal tubule. Also androgen antagonist may cause gynaecomastia

• These diuretics may cause hyperkalaemia

• Acetazolamide is a carbonic anhydrase inhibitor which results in bicarbonate loss and can cause metabolic acidosis while

All diuretics (apart from the potassium sparing diuretics) may cause hypokalaemia and precipitate digoxin toxicity 

Mannitol * is an osmotic diuretic and may be used following retention of hypotonic fluid, for instance in hyponatraemia following trans-cervical resection of endometrium

Top of Form

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download