Diuretic Drugs Diuretic Drugs Drugs that accelerate the rate of urine formation Result in the removal of sodium and water Used in the treatment of hypertension heart failure and renal failure Sodium In the nephron where sodium goes water follows o 60 to 70 of sodium and water is returned to bloodstream by the proximal tubule o 20 to 25 of all sodium is reabsorbed into the bloodstream in the ascending loop of Henle o 5 to 10 is reabsorbed in the distal tubules o 3 is reabsorbed in collecting ducts If water is not absorbed it is excreted as urine Types of Diuretic Drugs Carbonic anhydrase inhibitors Loop diuretics Osmotic diuretics Potassium sparing diuretics Thiazide and thiazide like diuretics Loop Diuretics bumetanide Bumex alternative ethacrynic acid Edecrin furosemide Lasix torsemide Demadex Mechanism of Action o Possess renal cardiovascular and metabolic effects o Act directly on the ascending limb of the loop of Henle to inhibit chloride and sodium resorption o Increase renal prostaglandins resulting in the dilation of blood vessels and reduced peripheral vascular resistance o Useful in treatment of edema o Normal 24 hour urine output is 800 2400 Drug Effects o Potent diuresis and subsequent loss of fluid o Decreased fluid volume causes a reduction in o Blood pressure o Pulmonary vascular resistance o Systemic vascular resistance o Central venous pressure o Left ventricular end diastolic pressure o Potassium and sodium depletion Indications o Edema associated with HF or hepatic or renal disease o To control hypertension o To increase renal excretion of calcium in patients with hypercalcemia o In cases of HF resulting from diastolic dysfunction o Excellent at treating ascites o Give in morning increases urinary output Adverse Effects o Central nervous system CNS Dizziness headache tinnitus blurred vision o Gastrointestinal GI Nausea vomiting diarrhea o Integumentary Stevens Johnson syndrome torsemide rare unless on it long term o Hematologic Agranulocytosis neutropenia thrombocytopenia o Metabolic Hypokalemia hyperglycemia hyperuricemia Osmotic Diuretics Examples mannitol Osmitrol Most used osmotic diuretic Urea Organic acids Glucose Mechanism of Action o Work mostly in the proximal tubule o Nonabsorbable producing an osmotic effect o Pull water into the renal tubules from the surrounding tissues o Inhibit tubular resorption of water and solutes thus producing rapid diuresis Drug Effects o Increases glomerular filtration rate and renal plasma flow helps to prevent kidney damage during acute renal failure o Reduces intracranial pressure or cerebral edema associated with head trauma o Reduces excessive intraocular pressure Indications o Treatment of patients in the early oliguric phase of acute renal failure ARF o To promote excretion of toxic substances o To reduce intracranial pressure o Treatment of cerebral edema o NOT indicated for peripheral edema Adverse Effects o Convulsions o Thrombophlebitis slow push o Pulmonary congestion o Also headaches chest pains tachycardia blurred vision chills and fever Mannitol Osmitrol o Intravenous infusion only o May crystallize when exposed to low temperatures o Use of a filter is required o Clear color no sediment Potassium Sparing Diuretics amiloride Midamor spironolactone Aldactone 1st prototype triamterene Dyrenium Also known as aldosterone inhibiting diuretics Mechanism of Action o Work in collecting ducts and distal convoluted tubules o Interfere with sodium potassium exchange o Competitively bind to aldosterone receptors o Block resorption of sodium and water usually induced by aldosterone Drug Effects o Prevent potassium from being pumped into the tubule thus preventing its secretion o Competitively block aldosterone receptors and inhibit their action o Promote the excretion of sodium and water Indications o spironolactone and triamterene Hyperaldosteronism excessive hair growth Hypertension Reversing potassium loss caused by potassium losing drugs Certain cases of HF o amiloride Treatment of HF Adverse Effects o CNS Dizziness headache o GI Cramps nausea vomiting diarrhea o Other Urinary frequency weakness hyperkalemia o spironolactone Aldactone Gynecomastia Amenorrhea Irregular menses Postmenopausal bleeding Thiazide and Thiazide like Diuretics Thiazide diuretics o hydrochlorothiazide Esidrix HydroDIURIL HCTZ o chlorothiazide Diuril Thiazide like diuretics o metolazone Mykrox Zaroxolyn o chlorthalidone Hydone Thalitone o indapamide Lozol Mechanism of Action o Inhibit tubular resorption of sodium chloride and potassium ions o Action primarily in the distal convoluted tubule o Result water sodium and chloride are excreted o Potassium is also excreted to a lesser extent o Dilate the arterioles by direct relaxation Drug Effects o Lowered peripheral vascular resistance o Depletion of sodium and water and potassium o Thiazides should not be used if creatinine clearance is less than 30 to 50 mL min normal is 125 mL min o Metolazone remains effective to a creatinine clearance of 10 mL min o Very few side effects Indications o Hypertension one of the most prescribed group of drugs for this o Edematous states o Idiopathic hypercalciuria don t see often o Diabetes insipidus o Heart failure due to diastolic dysfunction o Adjunct drugs in treatment of edema related to HF hepatic cirrhosis or corticosteroid or estrogen therapy Adverse Effects o CNS Dizziness headache blurred vision o GI Anorexia nausea vomiting diarrhea o GU Impotence o Hematologic Jaundice leukopenia o Integumentary Urticaria photosensitivity o Metabolic Hypokalemia hyperglycemia hyperuricemia hypochloremic alkalosis Nursing Implications Perform a thorough patient history and physical examination Assess baseline fluid volume status intake and output serum electrolyte values weight and vital signs especially postural BPs Assess for disorders that may contraindicate or necessitate cautious use of these drugs Instruct patients to take the medication in the morning if possible to avoid interference with sleep patterns Monitor serum potassium levels during therapy Teach patients to maintain proper nutritional and fluid volume status Teach patients to eat more potassium rich foods when taking any but the potassium sparing drugs o Foods high in potassium include bananas oranges dates apricots raisins broccoli green beans potatoes meats fish and legumes Patients taking diuretics along with a digitalis preparation should be taught to monitor for digitalis toxicity Patients with