Hyperkalemia spironolactone

Spironolactone Hyperkalemia hyponatremia gynecomastia agranulocytosis menstrual abnormalities GI disturbances rash... 

Potassium-sparing by diuretic agents, particularly spironolactone, enhances the effectiveness of other diuretics because the secondary hyperaldosteronism is blocked. This class of diuretics decreases magnesium excretion, eg, amiloride can decrease renal excretion of potassium up to 80%. The most important and dangerous adverse effect of all potassium-sparing diuretics is hyperkalemia, which can be potentially fatal the incidence is about 0.5% (50). Therefore, blood potassium concentrations should be monitored carehiUy. 

ACE inhibitors do not completely block aldosterone synthesis. Since this steroid hormone is a potent inducer of fibrosis in the heart, specific antagonists, such as spironolactone and eplerenone, have recently been very successfully used in clinical trials in addition to ACE inhibitors to treat congestive heart failure [5]. Formerly, these drugs have only been applied as potassium-saving diuretics in oedematous diseases, hypertension, and hypokalemia as well as in primary hyperaldosteronism. Possible side effects of aldosterone antagonists include hyperkalemia and, in case of spironolactone, which is less specific for the mineralocorticoid receptor than eplerenone, also antiandrogenic and progestational actions. 

Hyperkalemia (increase in potassium in the blood), a serious event, may be seen with the administration of potassium-sparing diuretics. Hyperkalemia is most likely to occur in patients with an inadequate fluid intake and urine output, those with diabetes or renal disease tiie elderly, and those who are severely ill. In patients taking spironolactone, gynecomastia (breast enlargement in tiie male) may occur. This reaction appears to be related to both dosage and duration of therapy. The gynecomastia is usually reversible when therapy is discontinued, but in rare instances, some breast enlargement may remain. 

The answer is e. (Hardman, p 708.) Spironolactone is a competitive antagonist of aldosterone that blocks the reabsorption of Na and water from the collecting duct in exchange for K and hydrogen ion retention. Therefore, in the presence of hyperkalemia, spironolactone is contraindicated The administration of each of the other diuretic agents listed results in increased excretion of K. 

Potassium-sparing diuretics may cause hyperkalemia, especially in patients with chronic kidney disease or diabetes, and in patients receiving concurrent treatment with an ACE inhibitor, ARB, NSAID, or potassium supplement. Eplerenone has an increased risk for hyperkalemia and is contraindicated in patients with impaired renal function or type 2 diabetes with proteinuria. Spironolactone may cause gynecomastia in up to 10% of patients, but this effect occurs rarely with eplerenone. 

Hyperkalemia Yasmin contains the progestin drospirenone that has antimineralocorticoid activity, including the potential for hyperkalemia in high-risk patients, comparable to a 25 mg dose of spironolactone. Yasmin should not be used in patients with conditions that predispose to hyperkalemia. Women receiving daily, long-term treatment for chronic conditions or diseases with medications that may increase serum potassium should have their serum potassium level checked during the first treatment cycle. 

A small increase (mean increase of 0.1 mEq/L) was observed in patients treated with candesartan alone but was rarely of clinical importance. One patient from a CHF trial was withdrawn for hyperkalemia (serum potassium, 7.5 mEq/L). This patient was also receiving spironolactone. 

Hyperkalemia Carefully evaluate patients for possible fluid and electrolyte balance disturbances. Hyperkalemia may occur with impaired renal function or excessive potassium intake and can cause cardiac irregularities that may be fatal. Ordinarily, do not give potassium supplements with spironolactone. 

Patients receiving spironolactone or amiloride anuria severe hepatic disease hyperkalemia hypersensitivity to triamterene severe or progressive kidney disease or dysfunction, with the possible exception of nephrosis preexisting elevated serum potassium (impaired renal function, azotemia) or patients who develop hyperkalemia while on triamterene. 

In patients with renal insufficiency, spironolactone may induce hyperkalemia. 

Spironolactone Block cytoplasmic aldosterone receptors in collecting tubules of nephron possible membrane effect Increased salt and water excretion reduces remodeling reduces mortality Chronic heart failure aldosteronism (cirrhosis, adrenal tumor) hypertension Oral duration 24-72 h (slow onset and offset) Toxicity Hyperkalemia, antiandrogen actions... 

Spironolactone as a diuretic is discussed in Chapter 15. The drug has benefits in heart failure greater than those predicted from its diuretic effects alone (see Chapter 13). Adverse effects reported for spironolactone include hyperkalemia, cardiac arrhythmia, menstrual abnormalities, gynecomastia, sedation, headache, gastrointestinal disturbances, and skin rashes. 

Eplerenone, another aldosterone antagonist, is approved for the treatment of hypertension (see Chapters 11 and 15). This aldosterone receptor antagonist is somewhat more selective than spironolactone and has no reported effects on androgen receptors. The standard dosage in hypertension is 50-100 mg/d. The most common toxicity is hyperkalemia but this is usually mild. 

Potassium-sparing diuretics (e.g., spironolactone, amiloride, triamterene) may cause a dangerous build-up of excessive potassium in the body. Signs of hyperkalemia, or excess potassium, include ... 

Potassium-sparing diuretics, such as amiloride (Midamor), spironolactone (Aldactone), and triamterene (Dyrenium), impair the ability of the kidneys to filter potassium from the body. This can result in a condition called hyperkalemia, or excessive potassium, a potentially dangerous situation (see Harmful side effects section). Anyone taking potassium-sparing diuretics should avoid excessive dietary intake of foods high in the mineral. Bananas, tomatoes, sweet potatoes, and oranges are some of the foods that are rich in potassium. 

Adverse effects Renal function may deteriorate with the decreased circulating fluid volume, especially after the addition of another diuretic drug acting on the RAAS system, and careful monitoring of serum creatinine is essential. Serum potassium should be monitored within one week of initiation and at least every four weeks for the first three months and every three months thereafter. It should also be monitored at any dose change in spironolactone or if there is a change in concomitant medications that affects the potassium balance. The spironolactone dose (standard 25 mg per day) should be reduced if potassium levels are <5.4 mEq/L, and treatment should be discontinued if painful gynecomastia or serious renal dysfunction or hyperkalemia result. 

Spironolactone should not be used concurrently with another potassiumsparing agent (e.g., amiloride, triamterene), or potassium-containing medications, or potassium supplements, or salt substitutes containing substantial amounts of potassium. Concomitant therapy with these drugs may increase the risk of hyperkalemia compared with spironolactone alone [65, 84]. 

Because indomethacin may increase serum potassium concentrations, indomethacin and spironolactone should be administered concomitantly with caution. Potassium-sparing diuretics should be used with caution, and serum potassium should be determined frequently in patients receiving an angiotensin-converting enzyme (ACE) inhibitor (e.g., captopril). Concomitant administration with an ACE inhibitor may increase the risk of hyperkalemia. The dosage of spironolactone should be reduced, or the drug discontinued, as necessary. Patients with renal impairment may be at increased risk of hyperkalemia [65]. 

Hyperkalemia May occur in up to 26% of patients receiving spironolactone, even when combined with thiazide diuretics. Irregular heartbeat is usually the earliest clinical indication of hyperkalemia, and is readily detected by ECG. Other signs and symptoms include confusion, nervousness, numbness or tingling in extremities (hands, feet, or lips), shortness of breath or difficult breathing, unusual tiredness or weakness, or weakness or heaviness of legs. 

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