There is a third class of diuretic that is referred to as potassiumsparing diuretics. Potassiumsparing diuretics potassiumsparing diuretics include amiloride and spironolactone. Furosemide contributes to loss of potassium through its effects on the distal nephron. Mechanism of action, pharmacokinetics, adverse effects. However, at low doses the use of potassium sparing diuretics has not been found to produce a. Owing to its potassium sparing effects, it may correct hypokalemia that pd patients experience. A combination of a potassium sparing diuretic with a thiazide diuretic is used to reduce edema due to salt and water retention in disorders of the heart, kidneys, liver or lungs.
Capitals indicate lifethreatening, underlines indicate most frequent. Loop diuretics act on the loop of henle in the kidney and prevent reab sorption of water and salt. Potassium sparing diuretics have weak diuretic and antihypertensive properties and are used mainly to conserve potassium in patients receiving thiazide or loop diuretics. They are occasionally used to counteract the potassium wasting effects of thiazides. Potassiumsparing agents during diuretic therapy in hypertension. High blood pressure linus pauling institute oregon. Amiloride, triamterene, and the spirolactones are potassiumsparing diuretics which act on the distal parts of the nephron, from the late distal tubule to. Osmotic diuretics helps to prevent the reabsorption of water and sodium in the body increase the amount of blood flowing into the kidneys prevent the urine to get concentrated used during heart problems.
Discontinue potassiumsparing diuretics 3 days prior to a glucose tolerance test becauseofriskofseverehyperkalemia. Potassiumsparing diuretics are medicines that increase diuresis urination without the loss of potassium. Pdf on mar 28, 2012, cristiana catena and others published potassium sparing diuretics in hypertension find, read and cite all the research you need on. Other side effects include gout, which results from raised uric acid levels hyperuricaemia table 2, fig. A potentially serious side effect of potassium sparing diuretics is hyperkalemia. Thiazide diuretics and loop diuretics are used alone or in combination in the treatment of hypertension or edema due to hf or other causes. Potassiumsparing diuretics an overview sciencedirect. The proper usage of potassium sparing diuretics in pd patients and data on the efficacy and safety are being explored. These medications decrease the amount of potassium lost in the urine and can make potassium levels too high, especially in people who have kidney problems. A new nonsteroidal mineralocorticoid blocker, finerenone, is currently in phase 3 clinical trials.
Used by themselves, potassium sparing diuretics exert only a mild diuretic effect because the collecting duct reabsorbs only 25% of filtered sodium. Clinical use of diuretics in heart failure, cirrhosis, and. Potassium sparing diuretics are often combined with either a loop diuretic or a thiazide diuretic. Pdf on mar 28, 2012, cristiana catena and others published potassiumsparing diuretics in hypertension find, read and cite all the research you need on researchgate. Potassium sparing diuretics in hypertension 69 aldosterone is a steroid hormone that is secreted by the zona glomerulosa of the adrenal cortex and is involved in regulation of blood pr essure exerting its main effects on the distal.
Amiloride acts about 2 hours after oral administration, reaching a peak in 610 hours and persisting for about 24 hours. Prevention and treatment of hypokalaemia management of resistant hypertension prevention of hypokalaemia is important in patients with cardiac arrhythmias, in patients requiring a thiazide or thiazidelike diuretic who have low potassium intake. Potassium sparing diuretics when used alone are rather weak, hence they are used most commonly in combination therapy with thiazide and loop diuretics. However, there is a risk of hyperkalemia high potassium levels if they are used with other agents that also retain potassium, such as ace inhibitors.
The potassiumsparing diuretics are very weak natriuretics indeed, capable of a maximum excretion of 12% of filtered sodium. Potassium sparing diuretics, which block the epithelial sodium channel enac, are widely prescribed for hypertension as a secondline drug in patients taking other diuretics e. Potassium sparing diuretics prevent excessive loss of potassium at the distal convoluted tubules. A combination of a potassium sparing diuretic with a thiazide diuretic is used to reduce edema due to salt and water retention in disorders of the heart, kidneys, liver. Pathophysiology of diureticinduced hypokalemia diuretics that either inhibit reabsorption in the thick ascending limb of henle drugs such as furosemide, ethacrynic acid, bumetanide or in the early distal tubule such as thiazides. Types of diuretic drugs osmotic diuretics carbonic anhydrse inhibitor benzothiazide loop diuretics potassium sparing diuretics 10. Thiazide diuretics uses, list, thiazide mechanism of action. In contrast, furosemide is highly effective despite renal impairment, although high doses are often needed when serum creatinine increases. The loopactive diuretics may cause hypokalemia, which can be countered by potassium supplementation or potassium sparing diuretics. Diuretics are often used to fight or prevent swelling in people with heart failure, but taking a potassium sparing diuretic helps. Traditionally, an important indication for potassium sparing diuretics is to prevent or attenuate k losses that are consequent to administration of dct or loop diuretics.
Its part thiazide, part potassium sparing diuretic. Diuretics are often used to fight or prevent swelling in people with heart failure, but taking a potassium sparing diuretic helps people with heart failure feel better, stay out of the hospital, and live longer. This sometimes requires treatment with potassium supplements or with a potassium sparing diuretic. A potential side effect of this activity is that they may cause electrolyte imbalances. Includes diuretics, potassiumsparing side effects, interactions and indications. Potassium sparing diuretics do not reduce blood pressure, but they also prevent a loss of potassium. Potassiumsparing diuretics are used, then, as part of combination therapy in the prevention treatment of hypokalemia.
For this reason, it is frequently taken alongside another diuretic such as a loop or thiazide diuretic to counteract potassium loss and promote overall diuresis. Combination tablets are more expensive but may improve compliance by reducing the number of tablets to be taken. Low potassium levels from diuretics harvard health. A special group of diuretics does the same job while preventing the loss of potassium, which is why theyre called. Potassiumsparing diuretics information, uses and side. Oct 04, 2018 loop diuretics and thiazide diuretics are stronger than potassium sparing diuretics with regard to making the kidneys pass out more fluid. Potassium sparing diuretics encourage the body to get rid of fluids and sodium. Carbonic anhydrase inhibitors work by increasing the excretion of sodium, potassium, bicarbonate and water from the renal tubules.
The potassiumsparing diuretics block the exchange processes in the distal tubule and thus prevent potassium loss. Potassium sparing diuretics often are used in conjunction with furosemide to prevent this complication. Potassium sparing diuretics university health network. Mar 05, 2019 potassiumsparing diuretics potassiumsparing diuretics, such as amiloride midamor and spironolactone aldactone, are used to treat high blood pressure and congestive heart failure. Potassium sparing diuretics potassium sparing diuretics include amiloride and spironolactone. We undertook this study to investigate the association between use of loop diuretics, thiazide or thiazidelike diuretics, and potassium sparing. Unlike loop and thiazide diuretics, some of these drugs do not act directly on. Potassiumsparing diuretics are often combined with either a loop diuretic or a thiazide diuretic. Diuretics are critical in the management of resistant hypertension, which affects approximately 5% of all adults and is a major contributor to morbidity and mortality. Amiloride hydrochloride is a new, orally administered, potassium. Pharmacology and clinical use of diuretics katie herndon, pharm. Potassium sparing diuretics information for patients read this medicine fact sheet to learn about.
Other side effects and drug interactions are list below. Potassium sparing diuretics free download as powerpoint presentation. Sometimes a mixture of diuretics is used in which a thiazide is taken together with a potassiumsparing diuretic to prevent excess potassium loss. Interactions between antihypertensive drugs and other medications. Oral diuretics and total abstinence from alcohol are both considered the second line of treatment.
This risk is increased when used in association with potassium supplements and salt substitutes, as previously noted. However, they also increase the amount of potassium passed out of the body through the kidneys. These unique properties result in biologic effects specific to drugs within the class that can be complementary to other diuretics, especially kaliuretic agents such as loop diuretics. If you take a thiazide diuretic, your potassium level can drop too low hypokalemia, which can cause lifethreatening problems with your heartbeat. Potassiumsparing diuretics are diuretic drugs that do not promote the secretion of potassium into the urine. Solution potassium sparing diuretics are weak diuretics that act in the collecting tubules.
Osmotic diuretics are lowmolecularweight substances that are. Because of its steroid hormonelike structure, spironolactone can mildly activate the nuclear receptors for testosterone and progesterone leading to gynecomastia and impotence in men as well as menstrual irregularities in women. Pdf potassiumsparing diuretics in hypertension leonardo. However, a nonsignificant trend favored the diuretic combination. Oct 19, 2019 diuretics can also affect blood potassium levels. Potassiumsparing diuretics such as spironolactone, amiloride, and triamterene all have the potential to cause hyperkalemia. Loop diuretics examples bumetamide furosemide torasemide.
Potassium sparing diuretics are probably underutilized. Many of the thiazide diuretics are also available in fixed dose combination with other antihypertensive medications or with potassium sparing diuretics. This patients serum potassium level is low, which can trigger fatal dysrhythmias, especially in patients taking digoxin. So, often, you see, these diuretics are given with loop diuretic or thiazide diuretic in order to prevent the hypokalemia done by thiazide and loop. Principles of diuretic action site of action is located on the luminal surface of the tubule extensively bound to serum albumin transported into the proximal tubule lumen by active secretion organic acid secretory pathway. The clinical pharmacology of potassium sparing diuretics is important. Concomitant administration of potassiumsparing diuretics and ace inhibitors or nonsteroidal anti inflammatory drugs nsaids, e. Introduction potassiumsparing diuretics prevent potassium secretion by antagonizing the effects of aldosterone in collecting tubules. Potassiumsparing diuretics pharmacology nursing mechanism. Monitor response of signs and symptoms of hypokalemia weakness, fatigue, u wave on ecg, arrhythmias, polyuria, polydipsia. The uses of potassium sparing diuretics are broadening, as negative effects of aldosterone in human disease are discovered. Potassiumsparing diuretics have weak diuretic and antihypertensive properties and are used mainly to conserve potassium in patients receiving thiazide or loop diuretics.
They are less potent diuretic agents therefore potassium sparing diuretics may combine with other diuretics to prevent the loss of potassium and further increase in diuretic effects. Potassium sparing refers to a type of diuretic medication. Potassiumsparing diuretics pharmacology the essential. They are generally weak diuretics and work by interfering with the sodiumpotassium exchange in the distal convoluted tubule of the kidneys or as an antagonist at the aldosterone receptor. However, this potassium sparing diuretic doesnt have much sodium to excrete, about 1 2%, and thats the reason, as we talked, this is weak diuretic than loop diuretic and thiazide diuretic. Jun 26, 1971 three pharmacological agents in use as potassiumsparing drugs have been tested by serial measurements of total exchangeable potassium k e during 4 to 12 weeks of oral diuretic therapy in hypertensive subjects. Assess patient frequently for development of hyperkalemia fatigue, muscle weakness, paresthesia, confusion, dyspnea, cardiac arrhythmias. The most concerning adverse effect of all potassium sparing diuretics is hyperkalemia that can rapidly become fatal as potassium levels rise. The potassium sparing diuretics are very weak natriuretics indeed, capable of a maximum excretion of 12% of filtered sodium.
Spironolactone is an example of potassium sparing diuretics, which are weak diuretics that act in the collecting tubules. Effect of potassiumsparing diuretics on the renin bmj heart. Spironolactone is the firstline diuretic recommended for a patient with cirrhosis and edema, initiating with a dose of 50 mg. List of potassium sparing diuretics with thiazides. Nonpotassium sparing diuretics university of toronto. Diuretics, potassiumsparing drug information, professional. Chronic therapy may be associated with hyperuricemia and gout, and possibly an increased risk of cholecystitis. Dyazide available as a generic is an attempt to strike a balance.
The most commonly used diuretics with a pronounced diuretic effect are thiazides, loop diuretics, and potassium sparing diuretics. Diuretics will lower blood pressure and potentiate the effects of aceis, arbs and other antihypertensive agents, including calcium. They are used as adjunctive therapy, together with other drugs, in the treatment of hypertension and management of congestive heart failure. They are used as adjunctive therapy, together with. A recent synthesis of 44 trials has shown that the relative potencies in milligrams among spironolactone spir, amiloride, and eplerenone epler are approximately. Role of potassiumsparing diuretics in the management of. Potassiumsparing diuretics an overview sciencedirect topics. Because potassium sparing diuretics do not promote the secretion of potassium during diuresis they do not cause hypokalemia low potassium levels. Diuretics help your body eliminate excess water, but most types also cause the loss of essential potassium along with the fluids. Potassium sparing diuretics are available as proprietary formulations combined with a thiazide or loop diuretics. Effect of potassiumsparing diuretics on the renin angiotensinaldosterone system and potassium retention in heart failure.
Potassiumsparing diuretics are diuretics that result in increased urine production and also lower blood pressure while increasing serum levels of potassium. Close monitoring of serum potassium is necessary in these circumstances. Potassium is an essential mineral that helps maintain fluid and electrolyte balance, influences blood pressure, and is required for proper nerve conduction and muscle contraction. In other instances, the potassium loss may read more. However, they do this without causing a loss of potassium, which is a vital nutrient. However, at low doses the use of potassium sparing diuretics has not been found to produce a clinically significant reduction in blood pressure. If you need this medicine for another problem, your health care provider will give you more information. Use of diuretics has been associated with an increased risk of gout. The most important and frequent problem with thiazide and loop diuretics is hypokalemia. Nonpostassium sparing diuretics may cause potassium a mineral in your body to be lost along with the fluid. Loop diuretics and potassium sparing diuretics have limited roles in the management of hypertension although accumulating evidence suggests that potassiumsparing diuretics may have an important place in apparently resistant hypertension. Non potassium sparing diuretics pronouced di uret ics.
List of potassiumsparing diuretics potassium sparing. C the eighth report of the joint national committee on prevention, detection, evaluation, and treatment of high blood pressure jnc8 guidelines reaffirmed the role of thiazide diuretics as one of the firstline treatment for hypertension. Potassium sparing diuretics nursing implications and drug study. Its primary site of action is the distal tubule of the nephron where it selectively blocks sodium transport, thereby inhibiting sodium. This is because they help to keep the right amount of potassium in your blood and they help other diuretics to remove fluid from the body. Clinical pharmacology in diuretic use american society. The potassium sparing diuretics act via mechanisms in the renal tubule that are distinct from those of other diuretic agents. Spironolactone is a direct, not indirect, acting diuretic. Triamterene seemed ineffective in the dosage used 50 mg twice daily. In a healthy person, the kidneys constantly filter the blood in the body. Taking a potassium sparing diuretic may be especially important if you have heart failure.
Trimethoprim was found to act like the potassium sparing diuretic amiloride and reduce renal potassium excretion. Amiloride acts about 2 hours after oral administration, reaching a peak. What this medicine is why you need to take it what side effects to watch for this fact sheet was created by the university health network pharmacy department. If youre on a potassium sparing diuretic, you can have too much potassium in your blood. Spironolactone is a weak diuretic that takes several days to take effect. Diuretics knowledge for medical students and physicians. Osmotic diuretics and carbonic anhydrase inhibitors are used in acute settings to lower intracranial andor intraocular pressure e. Potassium sparing diuretics are diuretic drugs that do not promote the secretion of potassium into the urine.
Recognition of this potassium disturbance led to the subsequent description of the mechanism by which trimethoprimsulfamethoxazole induced hyperkalemia. Osmotic diuretics are often used in the management of cerebral edema. Loop diuretics and potassium sparing diuretics have limited roles in the management of hypertension although accumulating evidence suggests that. Potassium sparing diuretics are diuretic drugs that do not promote the secretion of potassium into the urine they are used as adjunctive therapy, together with other drugs, in the treatment of hypertension and management of congestive heart failure. Potassium sparing diuretics include drugs that block apical sodium channels amiloride and triamterene and those that antagonize mineralocorticoid receptors spironolactone and eplerenone. Most of the blood enters into the nephrons everything except the big molecules like proteins and then your body reabsorbs the things you still need, like nutrients and fluids, back into your blood.