Hyperkalemia Like other potassium-conserving agents, amiloride may cause hyperkalemia (serum potassium levels greater than 5.5 mEq per liter) which, if uncorrected, is potentially fatal. Hyperkalemia occurs commonly (about 10%) when amiloride is used without a kaliuretic diuretic. This incidence is greater in patients with renal impairment, diabetes mellitus (with or without recognized renal insufficiency), and in the elderly. When amiloride hydrochloride is used concomitantly with a thiazide diuretic in patients without these complications, the risk of hyperkalemia is reduced to about 1 to 2 percent. It is thus essential to monitor serum potassium levels carefully in any patient receiving amiloride, particularly when it is first introduced, at the time of diuretic dosage adjustments, and during any illness that could affect renal function.
boxed warning
Hyperkalemia Like other potassium-conserving agents, amiloride may cause hyperkalemia (serum potassium levels greater than 5.5 mEq per liter) which, if uncorrected, is potentially fatal. Hyperkalemia occurs commonly (about 10%) when amiloride is used without a kaliuretic diuretic. This incidence is greater in patients with renal impairment, diabetes mellitus (with or without recognized renal insufficiency), and in the elderly. When amiloride hydrochloride is used concomitantly with a thiazide diuretic in patients without these complications, the risk of hyperkalemia is reduced to about 1 to 2 percent. It is thus essential to monitor serum potassium levels carefully in any patient receiving amiloride, particularly when it is first introduced, at the time of diuretic dosage adjustments, and during any illness that could affect renal function.
ADVERSE REACTIONS Amiloride hydrochloride is usually well tolerated and, except for hyperkalemia (serum potassium levels greater than 5.5 mEq per liter – see WARNINGS ), significant adverse effects have been reported infrequently. Minor adverse reactions were reported relatively frequently (about 20%) but the relationship of many of the reports to amiloride hydrochloride is uncertain and the overall frequency was similar in hydrochlorothiazide treated groups. Nausea/anorexia, abdominal pain, flatulence, and mild skin rash have been reported and probably are related to amiloride. Other adverse experiences that have been reported with amiloride are generally those known to be associated with diuresis, or with the underlying disease being treated. The adverse reactions for amiloride hydrochloride listed in the following table have been arranged into two groups: (1) incidence greater than one percent; and (2) incidence one percent or less. The incidence for group (1) was determined from clinical studies conducted in the United States (837 patients treated with amiloride hydrochloride). The adverse effects listed in group (2) include reports from the same clinical studies and voluntary reports since marketing. The probability of a causal relationship exists between amiloride hydrochloride and these adverse reactions, some of which have been reported only rarely. Incidence > 1% Incidence ≤ 1% Body as a Whole Headache* Back pain Weakness Chest pain Fatigability Neck/shoulder ache Pain, extremities Cardiovascular None Angina pectoris Orthostatic hypotension Arrhythmia Palpitation Digestive Nausea/anorexia* Jaundice Diarrhea* GI bleeding Vomiting* Abdominal fullness Abdominal pain GI disturbance Gas pain Thirst Appetite changes Heartburn Constipation Flatulence Dyspepsia Metabolic Elevated serum potassium levels (>5.5 mEq per liter)** None Skin None Skin rash Itching Dryness of mouth Pruritus Alopecia Musculoskeletal Muscle cramps Joint pain Leg ache Nervous Dizziness Paresthesia Encephalopathy Tremors Vertigo Psychiatric None Nervousness Mental confusion Insomnia Decreased libido Depression Somnolence Respiratory Cough Shortness of Breath Dyspnea Special Senses None Visual disturbances Nasal congestion Tinnitus Increased intraocular pressure Urogenital Impotence Polyuria Dysuria Urinary frequency Bladder spasms Gynecomastia *Reactions occurring in 3% to 8% of patients treated with amiloride hydrochloride. (Those reactions occurring in less than 3% of the patients are unmarked.) **See WARNINGS . Causal Relationship Unknown Other reactions have been reported but occurred under circumstances where a causal relationship could not be established. However, in these rarely reported events, that possibility cannot be excluded. Therefore, these observations are listed to serve as alerting information to physicians. Activation of probable pre-existing peptic ulcer Aplastic anemia Neutropenia Abnormal liver function
adverse reactions table
<table border="1" cellpadding="0" cellspacing="0" width="584px"><tbody><tr><td><paragraph><content styleCode="bold">Incidence > 1% </content></paragraph></td><td><paragraph><content styleCode="bold">Incidence </content><content styleCode="bold">≤</content><content styleCode="bold">1%</content></paragraph></td></tr><tr><td><paragraph><content styleCode="bold"><content styleCode="italics">Body as a Whole</content></content></paragraph></td><td><paragraph/></td></tr><tr><td><paragraph>Headache*</paragraph></td><td><paragraph>Back pain</paragraph></td></tr><tr><td><paragraph>Weakness</paragraph></td><td><paragraph>Chest pain</paragraph></td></tr><tr><td><paragraph>Fatigability</paragraph></td><td><paragraph>Neck/shoulder ache</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Pain, extremities</paragraph></td></tr><tr><td><paragraph><content styleCode="bold"><content styleCode="italics">Cardiovascular</content></content></paragraph></td><td><paragraph/></td></tr><tr><td><paragraph>None</paragraph></td><td><paragraph>Angina pectoris</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Orthostatic hypotension</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Arrhythmia</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Palpitation</paragraph></td></tr><tr><td><paragraph><content styleCode="bold"><content styleCode="italics">Digestive</content></content></paragraph></td><td><paragraph/></td></tr><tr><td><paragraph>Nausea/anorexia*</paragraph></td><td><paragraph>Jaundice</paragraph></td></tr><tr><td><paragraph>Diarrhea*</paragraph></td><td><paragraph>GI bleeding</paragraph></td></tr><tr><td><paragraph>Vomiting*</paragraph></td><td><paragraph>Abdominal fullness</paragraph></td></tr><tr><td><paragraph>Abdominal pain</paragraph></td><td><paragraph>GI disturbance</paragraph></td></tr><tr><td><paragraph>Gas pain</paragraph></td><td><paragraph>Thirst</paragraph></td></tr><tr><td><paragraph>Appetite changes</paragraph></td><td><paragraph>Heartburn</paragraph></td></tr><tr><td><paragraph>Constipation</paragraph></td><td><paragraph>Flatulence</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Dyspepsia</paragraph></td></tr><tr><td><paragraph><content styleCode="bold"><content styleCode="italics">Metabolic </content></content>Elevated serum potassium levels (>5.5 mEq per liter)** </paragraph></td><td><paragraph>None</paragraph></td></tr><tr><td><paragraph><content styleCode="bold"><content styleCode="italics">Skin</content></content></paragraph></td><td><paragraph/></td></tr><tr><td><paragraph>None</paragraph></td><td><paragraph>Skin rash</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Itching</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Dryness of mouth</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Pruritus</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Alopecia</paragraph></td></tr><tr><td><paragraph><content styleCode="bold"><content styleCode="italics">Musculoskeletal</content></content></paragraph></td><td><paragraph/></td></tr><tr><td><paragraph>Muscle cramps</paragraph></td><td><paragraph>Joint pain</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Leg ache</paragraph></td></tr><tr><td><paragraph><content styleCode="bold"><content styleCode="italics">Nervous</content></content></paragraph></td><td><paragraph/></td></tr><tr><td><paragraph>Dizziness</paragraph></td><td><paragraph>Paresthesia</paragraph></td></tr><tr><td><paragraph>Encephalopathy</paragraph></td><td><paragraph>Tremors</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Vertigo</paragraph></td></tr><tr><td><paragraph><content styleCode="bold"><content styleCode="italics">Psychiatric</content></content></paragraph></td><td><paragraph/></td></tr><tr><td><paragraph>None</paragraph></td><td><paragraph>Nervousness</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Mental confusion</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Insomnia</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Decreased libido</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Depression</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Somnolence</paragraph></td></tr><tr><td><paragraph><content styleCode="bold"><content styleCode="italics">Respiratory</content></content></paragraph></td><td><paragraph/></td></tr><tr><td><paragraph>Cough</paragraph></td><td><paragraph>Shortness of Breath</paragraph></td></tr><tr><td><paragraph>Dyspnea</paragraph></td><td><paragraph/></td></tr><tr><td><paragraph><content styleCode="bold"><content styleCode="italics">Special Senses</content></content></paragraph></td><td><paragraph/></td></tr><tr><td><paragraph>None</paragraph></td><td><paragraph>Visual disturbances</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Nasal congestion</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Tinnitus</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Increased intraocular pressure</paragraph></td></tr><tr><td><paragraph><content styleCode="bold"><content styleCode="italics">Urogenital</content></content></paragraph></td><td><paragraph/></td></tr><tr><td><paragraph>Impotence</paragraph></td><td><paragraph>Polyuria</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Dysuria</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Urinary frequency</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Bladder spasms</paragraph></td></tr><tr><td><paragraph/></td><td><paragraph>Gynecomastia</paragraph></td></tr><tr><td colspan="2"><paragraph>*Reactions occurring in 3% to 8% of patients treated with amiloride hydrochloride.</paragraph><paragraph>(Those reactions occurring in less than 3% of the patients are unmarked.)</paragraph><paragraph>**See <content styleCode="bold">WARNINGS</content>. </paragraph></td></tr></tbody></table>