TORSEMIDE (tor'se-mide)
Demadex Classifications: electrolyte and water balance agent; loop diuretic; Therapeutic: diuretic; antihypertensive Prototype: Furosemide Pregnancy Category: B
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Availability
5 mg, 10 mg, 20 mg, 100 mg tablets; 10 mg/mL injection
Action
Long-acting potent sulfonamide "loop" diuretic that inhibits reabsorption of sodium and chloride primarily in the
loop of Henle and also in the proximal and distal renal tubules. Binds to the sodium/potassium/chloride carrier in the
loop of Henle and in the renal tubules.
Therapeutic Effect
Long-acting potent sulfonamide "loop" diuretic and antihypertensive agent.
Uses
Management of edema associated with CHF, chronic kidney failure, hepatic cirrhosis; hypertension.
Contraindications
Hypersensitivity to torsemide or sulfonamides; anuria, fluid and electrolyte depletion states; acute MI; hepatic coma.
Cautious Use
Renal impairment; ventricular arrhythmias; concurrent use of other ototoxic drugs; gout or hyperuricemia; diabetes mellitus
or history of pancreatitis; liver disease; hearing impairment; pregnancy (category B); lactation.
Route & Dosage
Edema of CHF, Chronic Kidney Failure Adult: PO/IV 1020 mg once daily, may increase up to 200 mg/d as needed
Hepatic Cirrhosis Adult: PO/IV 510 mg once daily administered with an aldosterone antagonist or potassium-sparing diuretic, may increase up to 40
mg/d as needed
Hypertension Adult: PO 2.55 mg once daily, may increase to 10 mg/d if no response after 46 wk
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Administration
- Note: With hepatic cirrhosis, use an aldosterone antagonist concomitantly to prevent hypokalemia and metabolic alkalosis.
Oral
- Be aware that oral and IV doses are therapeutically equivalent; patients may be switched between the two forms with no change
in dosage.
Intravenous PREPARE: Direct: Given undiluted.
ADMINISTER: Direct: Give slowly over 2 min.
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INCOMPATIBILITIES Solution/additive: Dobutamine.
- Store at 15°30° C (59°86° F).
Adverse Effects (≥1%)
CNS: Headache, dizziness,
fatigue,
insomnia.
CV: Orthostatic hypotension.
Endocrine: Hypokalemia, hyponatremia, hyperuricemia.
GI: Nausea,
diarrhea.
Skin: Rash, pruritus.
Body as a Whole: Muscle cramps, rhinitis.
Interactions
Drug: nsaids may reduce diuretic effects. Also see
furosemide for potential drug interactions such as increased risk of
digoxin toxicity due to hypokalemia, prolonged neuromuscular blockade with
neuromuscular blocking agents, and decreased
lithium elimination with increased
toxicity.
Herbal: Ginseng may decrease
efficacy.
Pharmacokinetics
Absorption: Readily from GI tract.
Onset: IV 10 min; PO 60 min.
Peak: IV within 60 min; PO 60120 min.
Duration: 68 h.
Metabolism: In liver (CYP system).
Elimination: 80% in bile; 20% in urine.
Half-Life: 210 min.
Nursing Implications
Assessment & Drug Effects
- Monitor BP often and assess for orthostatic hypotension; assess respiratory status for S&S of pulmonary edema.
- Monitor ECG, as electrolyte imbalances predispose to cardiac arrhythmias.
- Lab tests: Monitor serum electrolytes, uric acid, blood glucose, BUN, and creatinine periodically throughout the course
of therapy.
- Monitor I & O with daily weights. Assess for improvement in edema.
- Monitor diabetics for loss of glycemic control.
- Monitor coagulation parameters and lithium levels in patients on concurrent anticoagulant and/or lithium therapy.
Patient & Family Education
- Check weight at least weekly and report abrupt gains or losses to physician.
- Understand the risk of orthostatic hypotension.
- Report symptoms of hypokalemia (see Appendix F) or hearing loss immediately to physician.
- Monitor blood glucose for loss of glycemic control if diabetic.