Classifications: electrolytic and water balance agent; loop diuretic; antihypertensive; Therapeutic: loop diuretic; antihypertensive
Pregnancy Category: B
25 mg, 50 mg tablet; 50 mg injection
Inhibits sodium and chloride reabsorption in proximal tubule and most segments of loop of Henle, promotes potassium and hydrogen
ion excretion, and decreases urinary ammonium ion concentration as well as pH of the blood. Promotes calcium elimination in
hypercalcemia and nephrogenic diabetes insipidus. Hypotensive effect may be due to hypovolemia secondary to diuresis and in
part to decreased vascular resistance.
Rapid and potent diuretic effect resulting in hypotensive effect. Fluid and electrolyte loss may exceed that caused by thiazides.
Severe edema associated with CHF, hepatic cirrhosis, ascites of malignancy, kidney disease, nephrotic syndrome, lymphedema.
Treatment of nephrogenic diabetes insipidus, hypercalcemia, mild to moderate hypertension, and as adjunct in therapy of hypertensive
crisis complicated by pulmonary edema.
History of hypersensitivity to ethacrynic acid; increasing azotemia, anuria; hepatic coma; severe diarrhea, dehydration, electrolyte
imbalance, hypotension; lactation, infants, and neonates; parenteral use in pediatric patients.
Hepatic cirrhosis; older adult cardiac patients; diabetes mellitus; history of gout; pulmonary edema associated with acute
MI; hyperaldosteronism; nephrotic syndrome; history of pancreatitis; pregnancy (category B).
Route & Dosage
Adult: PO 50100 mg 12 times/d, may increase by 2550 mg prn up to 400 mg/d IV 0.51 mg/kg or 50 mg up to 100 mg, may repeat if necessary
Child: PO 1 mg/kg q.d., may increase to 3 mg/kg/d
- Give after a meal or food to prevent gastric irritation.
- Schedule doses to avoid nocturia and thus sleep interference. Avoid administration within at least 4 h of bedtime, if possible.
This recommendation may not apply to the patient who accumulates fluid and develops respiratory symptoms during sleep.
PREPARE: Direct/Intermittent: Reconstitute by adding 50 mL of D5W or NS to vial. Use solution within 24 h. Vials reconstituted with D5W may turn cloudy;
if so, discard the vial.
ADMINISTER: Direct: Give at a rate of 10 mg/min. Intermittent: Give over 1530 min. If a second IV dose is required, a new site should be selected to prevent thrombophlebitis.
INCOMPATIBILITIES Solution/additive: Hydralazine, procainamide, ranitidine, tolazoline, triflupromazine.
- Store oral and parenteral form at 15°30° C (59°86° F) unless otherwise directed.
Adverse Effects (≥1%)CNS:
, apprehension, confusion. CV: Postural hypotension
(dizziness, light-headedness). Metabolic:
hypochloremic alkalosis, hypomagnesemia, hypocalcemia, hypercalciuria, hyperuricemia, hypovolemia, hematuria, glycosuria,
hyperglycemia, gynecomastia, elevated BUN, creatinine
, and urate levels. Special Senses:
Vertigo, tinnitus, sense of fullness in ears, temporary or permanent deafness. GI:
, nausea, vomiting, dysphagia, abdominal discomfort or pain, GI bleeding (IV
use), abnormal liver function
tests. Hematologic: Thrombocytopenia, agranulocytosis
(rare), severe neutropenia
Skin rash, pruritus. Body as a Whole:
Fever, chills, acute gout; local irritation and thrombophlebitis with IV
InteractionsDrug: thiazide diuretics
increase potassium loss; increased risk of digoxin toxicity
from hypokalemia; corticosteroids
, amphotericin B
increase risk of hypokalemia; decreased lithium
clearance, so increased risk of lithium toxicity
effect may be blunted, causing hyperglycemia; antihypertensive agents
increase risk of orthostatic hypotension; aminoglycosides
may increase risk of ototoxicity; warfarin
Rapidly absorbed from GI tract. Onset:
30 min PO; 5 min IV
2 h PO; 1530 min IV
68 h PO; 2 h IV
Does not cross CSF. Metabolism:
Metabolized to cysteine conjugate. Elimination:
3065% in urine; 3540% in bile. Half-Life:
Assessment & Drug Effects
- Observe closely when receiving the drug by IV infusion. Rapid, copious diuresis following IV administration can produce hypotension.
- Monitor IV site closely. Extravasation of IV drug causes local pain and tissue irritation from dehydration and blood volume
- Monitor BP during initial therapy. Because orthostatic hypotension can occur, supervise ambulation.
- Monitor BP and pulse throughout therapy in patients with impaired cardiac function. Diuretic-induced hypovolemia may reduce
cardiac output, and electrolyte loss promotes cardiotoxicity in those receiving digitalis (cardiac) glycosides.
- Establish baseline weight prior to start of therapy; weigh patient under standard conditions. Keep physician informed of weight
loss or gain in excess of 1 kg (2 lb)/d.
- Monitor I&O ratio. Drug should be discontinued if excessive diuresis, oliguria, hematuria, or sudden profuse diarrhea occurs.
Report signs to physician.
- Lab tests: Determine baseline and periodic blood count, serum electrolytes, CO2, BUN, creatinine, blood glucose, uric acid, and liver function.
- Observe for and report S&S of electrolyte imbalance: Anorexia, nausea, vomiting, thirst, dry mouth, polyuria, oliguria, weakness,
fatigue, dizziness, faintness, headache, muscle cramps, paresthesias, drowsiness, mental confusion. Instruct patient to report
these symptoms promptly to physician.
- Report immediately possible signs of thromboembolic complications (see Appendix F).
- Impaired glucose tolerance with hyperglycemia and glycosuria has occurred in patients receiving doses in excess of 200 mg/d.
Patient & Family Education
- Learn S&S of hypokalemia and hyponatremia (see Appendix F), and report any of these promptly to physician.
- Make position changes slowly, particularly from lying to upright posture.
- Report GI adverse effects to physician; they occur most frequently after 13 mo of PO therapy or in patients on high
dosage. The onset of loose stools or other GI symptoms at any time during therapy indicates possible need for dosage adjustment
or discontinuation of drug.
- Notify physician immediately of any evidence of impaired hearing. Hearing loss may be preceded by vertigo, tinnitus, or fullness
in ears; it may be transient, lasting 124 h, or it may be permanent.