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Pronunciation
(TORE se mide)
Generic Available (U.S.)
Yes
U.S. Brand Names
Pharmacologic Category
Pharmacologic Category Synonyms
Use: Labeled Indications
Management of edema associated with heart failure and hepatic or renal disease (including chronic renal failure); treatment of hypertension
Pregnancy Risk Factor
B
Pregnancy Considerations
A decrease in fetal weight, an increase in fetal resorption, and delayed fetal ossification has occurred in animal studies.
Lactation
Excretion in breast milk unknown/use caution
Contraindications
Hypersensitivity to torsemide, any component of the formulation, or any sulfonylurea; anuria
Warnings/Precautions
Concerns related to adverse effects:
• Fluid/electrolyte loss: Loop diuretics are potent diuretics; excess amounts can lead to profound diuresis with fluid and electrolyte loss; close medical supervision and dose evaluation are required. Potassium supplementation and/or use of potassium-sparing diuretics may be necessary to prevent hypokalemia.
• Nephrotoxicity: Monitor fluid status and renal function in an attempt to prevent oliguria, azotemia, and reversible increases in BUN and creatinine; close medical supervision of aggressive diuresis required.
• Ototoxicity: Ototoxicity has been demonstrated following oral administration of torsemide and following rapid I.V. administration of other loop diuretics. Other possible risk factors may include use in renal impairment, excessive doses, and concurrent use of other ototoxins (eg, aminoglycosides).
• Sulfa allergy: Chemical similarities are present among sulfonamides, sulfonylureas, carbonic anhydrase inhibitors, thiazides, and loop diuretics (except ethacrynic acid). Use in patients with sulfonylurea allergy is specifically contraindicated in product labeling; a risk of cross-reaction exists in patients with allergy to any of these compounds; avoid use when previous reaction has been severe. Discontinue if signs of hypersensitivity are noted.
Disease-related concerns:
• Cirrhosis: Use with caution in patients with cirrhosis; avoid sudden changes in fluid and electrolyte balance and acid/base status which may lead to hepatic encephalopathy. Administration with an aldosterone antagonist or potassium-sparing diuretic may provide additional diuretic efficacy and maintain normokalemia.
Concurrent drug therapy issues:
• Antihypertensives: Coadministration of antihypertensives may increase the risk of hypotension.
Adverse Reactions
1% to 10%:
Cardiovascular: ECG abnormality (2%), chest pain (1%)
Central nervous system: Nervousness (1%)
Gastrointestinal: Constipation (2%), diarrhea (2%), dyspepsia (2%), nausea (2%), sore throat (2%)
Genitourinary: Excessive urination (7%)
Neuromuscular & skeletal: Arthralgia (2%), myalgia (2%), weakness (2%)
Respiratory: Rhinitis (3%), cough (2%)
<1%, postmarketing, and/or case reports: Angioedema, arthritis, atrial fibrillation, esophageal hemorrhage, GI hemorrhage, hyperglycemia, hypernatremia, hyperuricemia, hypokalemia, hypotension, hypovolemia, impotence, leukopenia, rash, rectal bleeding, shunt thrombosis, Stevens-Johnson syndrome, syncope, thirst, thrombocytopenia, toxic epidermal necrolysis, ventricular tachycardia, vomiting
Metabolism/Transport Effects
Substrate of CYP2C8 (minor), CYP2C9 (major), SLCO1B1; Inhibits CYP2C19 (weak)
Drug Interactions
ACE Inhibitors: Loop Diuretics may enhance the hypotensive effect of ACE Inhibitors. Specifically, postural hypotension which can accompany ACE Inhibitor initiation. Loop Diuretics may enhance the nephrotoxic effect of ACE Inhibitors. Risk C: Monitor therapy
Allopurinol: Loop Diuretics may enhance the adverse/toxic effect of Allopurinol. Loop Diuretics may increase the serum concentration of Allopurinol. Specifically, Loop Diuretics may increase the concentration of Oxypurinolol, an active metabolite of Allopurinol. Risk C: Monitor therapy
Amifostine: Antihypertensives may enhance the hypotensive effect of Amifostine. Management: When amifostine is used at chemotherapy doses, antihypertensive medications should be withheld for 24 hours prior to amifostine administration. If antihypertensive therapy can not be withheld, amifostine should not be administered. Risk D: Consider therapy modification
Aminoglycosides: Loop Diuretics may enhance the adverse/toxic effect of Aminoglycosides. Specifically, nephrotoxicity and ototoxicity. Risk C: Monitor therapy
Antihypertensives: May enhance the hypotensive effect of other Antihypertensives. Risk C: Monitor therapy
Beta2-Agonists: May enhance the hypokalemic effect of Loop Diuretics. Risk C: Monitor therapy
Bile Acid Sequestrants: May decrease the absorption of Loop Diuretics. Risk D: Consider therapy modification
CISplatin: Loop Diuretics may enhance the nephrotoxic effect of CISplatin. Loop Diuretics may enhance the ototoxic effect of CISplatin. Risk C: Monitor therapy
Corticosteroids (Orally Inhaled): May enhance the hypokalemic effect of Loop Diuretics. Risk C: Monitor therapy
Corticosteroids (Systemic): May enhance the hypokalemic effect of Loop Diuretics. Risk C: Monitor therapy
CYP2C9 Inducers (Highly Effective): May increase the metabolism of CYP2C9 Substrates (High risk). Risk C: Monitor therapy
CYP2C9 Inhibitors (Moderate): May decrease the metabolism of CYP2C9 Substrates (High risk). Risk C: Monitor therapy
CYP2C9 Inhibitors (Strong): May decrease the metabolism of CYP2C9 Substrates (High risk). Risk D: Consider therapy modification
Diazoxide: May enhance the hypotensive effect of Antihypertensives. Risk C: Monitor therapy
Dofetilide: Loop Diuretics may enhance the QTc-prolonging effect of Dofetilide. Risk C: Monitor therapy
Eltrombopag: May increase the serum concentration of OATP1B1/SLCO1B1 Substrates. Management: According to eltrombopag prescribing information, consideration of a preventative dose reduction may be warranted. Risk D: Consider therapy modification
Fosphenytoin: May diminish the diuretic effect of Loop Diuretics. Risk C: Monitor therapy
Herbs (Hypertensive Properties): May diminish the antihypertensive effect of Antihypertensives. Risk C: Monitor therapy
Herbs (Hypotensive Properties): May enhance the hypotensive effect of Antihypertensives. Risk C: Monitor therapy
Hypotensive Agents: May enhance the adverse/toxic effect of other Hypotensive Agents. Risk C: Monitor therapy
Licorice: May enhance the hypokalemic effect of Loop Diuretics. Risk C: Monitor therapy
Lithium: Loop Diuretics may decrease the serum concentration of Lithium. Loop Diuretics may increase the serum concentration of Lithium. Risk C: Monitor therapy
MAO Inhibitors: May enhance the orthostatic hypotensive effect of Orthostatic Hypotension Producing Agents. Risk C: Monitor therapy
Methylphenidate: May diminish the antihypertensive effect of Antihypertensives. Risk C: Monitor therapy
Neuromuscular-Blocking Agents: Loop Diuretics may diminish the neuromuscular-blocking effect of Neuromuscular-Blocking Agents. Loop Diuretics may enhance the neuromuscular-blocking effect of Neuromuscular-Blocking Agents. Risk C: Monitor therapy
Nonsteroidal Anti-Inflammatory Agents: May diminish the diuretic effect of Loop Diuretics. Risk C: Monitor therapy
Peginterferon Alfa-2b: May decrease the serum concentration of CYP2C9 Substrates (High risk). Risk C: Monitor therapy
Pentoxifylline: May enhance the hypotensive effect of Antihypertensives. Risk C: Monitor therapy
Phenytoin: May diminish the diuretic effect of Loop Diuretics. Risk C: Monitor therapy
Phosphodiesterase 5 Inhibitors: May enhance the antihypertensive effect of Antihypertensives. Risk C: Monitor therapy
Probenecid: May enhance the adverse/toxic effect of Loop Diuretics. Probenecid may diminish the diuretic effect of Loop Diuretics. Probenecid may increase the serum concentration of Loop Diuretics. Management: Monitor for decreased diuretic effects or increased adverse effects of loop diuretics with concomitant use of probenecid. Bumetanide prescribing information recommends against concomitant use of probenecid. Risk C: Monitor therapy
Prostacyclin Analogues: May enhance the hypotensive effect of Antihypertensives. Risk C: Monitor therapy
RiTUXimab: Antihypertensives may enhance the hypotensive effect of RiTUXimab. Risk D: Consider therapy modification
Salicylates: May diminish the diuretic effect of Loop Diuretics. Loop Diuretics may increase the serum concentration of Salicylates. Risk C: Monitor therapy
Sodium Phosphates: Diuretics may enhance the nephrotoxic effect of Sodium Phosphates. Specifically, the risk of acute phosphate nephropathy may be enhanced. Management: Consider avoiding this combination by temporarily suspending treatment with diuretics, or seeking alternatives to oral sodium phosphate bowel preparation. If the combination cannot be avoided, hydrate adequately and monitor fluid and renal status. Risk D: Consider therapy modification
Warfarin: Torsemide may increase the serum concentration of Warfarin. Risk C: Monitor therapy
Yohimbine: May diminish the antihypertensive effect of Antihypertensives. Risk C: Monitor therapy
Ethanol/Nutrition/Herb Interactions
Herb/Nutraceutical: Avoid herbs with hypertensive properties (bayberry, blue cohosh, cayenne, ephedra, ginger, ginseng [American], kola, licorice); may diminish the antihypertensive effect of torsemide. Avoid herbs with hypotensive properties (black cohosh, California poppy, coleus, golden seal, hawthorn, mistletoe, periwinkle, quinine, shepherd's purse); may enhance the hypotensive effect of torsemide.
Storage
I.V.: Store at 15°C to 30°C (59°F to 86°F). If torsemide is to be administered via continuous infusion, stability has been demonstrated through 24 hours at room temperature in plastic containers for the following fluids and concentrations:
200 mg torsemide (10 mg/mL) added to 250 mL D5W, 250 mL NS or 500 mL 0.45% sodium chloride
50 mg torsemide (10 mg/mL) added to 500 mL D5W, 500 mL NS, or 500 mL 0.45% sodium chloride
Tablets: Store at 15°C to 30°C (59°F to 86°F).
Compatibility
Stable in D5W, NS, 1/2NS.
Y-site administration: Compatible: Milrinone, nesiritide.
Compatibility when admixed: Incompatible with dobutamine.
Mechanism of Action
Inhibits reabsorption of sodium and chloride in the ascending loop of Henle and distal renal tubule, interfering with the chloride-binding cotransport system, thus causing increased excretion of water, sodium, chloride, magnesium, and calcium; does not alter GFR, renal plasma flow, or acid-base balance
Pharmacodynamics/Kinetics
Onset of action: Diuresis: Oral: Within 1hour
Peak effect: Diuresis: Oral: 1-2 hours; Antihypertensive: Oral: 4-6 weeks (up to 12 weeks)
Duration: Diuresis: Oral: ~6-8 hours
Absorption: Oral: Rapid
Distribution: Vd: 12-15 L; Cirrhosis: Approximately doubled
Protein binding: >99%
Metabolism: Hepatic (~80%) via CYP
Bioavailability: ~80%
Half-life elimination: ~3.5 hours; Cirrhosis: 7-8 hours
Time to peak, plasma: Oral: 1 hour; delayed ~30 minutes when administered with food
Excretion: Urine (~20% as unchanged drug)
Dosage
Adults: Note: I.V. and oral dosing are equivalent.
Edema:
Chronic renal failure: Oral, I.V.: Initial: 20 mg once daily; may increase gradually by doubling dose until the desired diuretic response is obtained (maximum recommended daily dose: 200 mg)
Heart failure:
Oral: Initial: 10-20 mg once daily; may increase gradually by doubling dose until the desired diuretic response is obtained. Note: ACC/AHA 2009 guidelines for heart failure maximum daily dose: 200 mg (Hunt, 2009)
I.V.: Initial: 10-20 mg; may repeat every 2 hours with double the dose as needed. Note: ACC/AHA 2009 guidelines for heart failure recommend maximum single dose: 100-200 mg (Hunt, 2009)
Continuous I.V. infusion (unlabeled dose): Initial: 20 mg I.V. load, then 5-20 mg/hour (Hunt, 2009)
Hepatic cirrhosis: Oral: Initial: 5-10 mg once daily; may increase gradually by doubling dose until the desired diuretic response is obtained (maximum recommended single dose: 40 mg). Note: Administer with an aldosterone antagonist or a potassium-sparing diuretic.
Hypertension: Oral: Initial: 5 mg once daily; may increase to 10 mg once daily after 4-6 weeks if adequate antihypertensive response is not apparent; if still not effective, an additional antihypertensive agent may be added. Usual dosage range (JNC 7): 2.5-10 mg once daily. Note: Thiazide-type diuretics are preferred in the treatment of hypertension (Chobanian, 2003)
Administration: Oral
Administer without regard to meals; patients may be switched from the I.V. form to the oral (and vice-versa) with no change in dose.
Administration: I.V.
Administer over ≥2 minutes; reserve I.V. administration for situations which require rapid onset of action.
Administration: I.V. Detail
pH: >8.3
Monitoring Parameters
Renal function, electrolytes, and fluid status (weight and I & O), blood pressure
Dietary Considerations
May be taken without regard to meals; however, food slows the rate and reduces the extent of absorption and may reduce diuretic efficacy (Bard, 2004). May require increased intake of potassium-rich foods.
Patient Education
Take with food or milk (to reduce GI distress), early in the day. If taken twice daily, take last dose in early afternoon in order to avoid sleep disturbance and achieve maximum therapeutic effect. Include potassium-rich foods in daily diet. Do not take potassium supplements without consulting prescriber. Weigh yourself each day when beginning therapy and weekly on long-term therapy; report unusual or unanticipated weight gain or loss. May cause transient drowsiness, blurred vision, dizziness, or constipation. Report unusual weight gain or loss, swelling of ankles and hands, persistent fatigue, weakness, fatigue, dizziness, vomiting, cramps, change in hearing, or chest pain or palpitations.
Geriatric Considerations
Loop diuretics are potent diuretics, excess amounts can lead to profound diuresis with fluid and electrolyte loss. Close medical supervision and dose evaluation is required, particularly in elderly.
Additional Information
10-20 mg torsemide is approximately equivalent to furosemide 40 mg or bumetanide 1 mg.
Anesthesia and Critical Care Concerns/Other Considerations
Clinical Pearls/Comments: If given the morning of surgery, it may render the patient volume depleted and blood pressure may be labile during general anesthesia. Torsemide may induce potent diuretic effects and, as with other potent diuretics, electrolytes and volume status needs to be closely monitored.
Dose equivalency (approximate): Bumetanide 1 mg = furosemide 40 mg = torsemide 10 mg
Cardiovascular Considerations
Torsemide may induce potent diuretic effects and, as with other potent diuretics, electrolytes and volume status needs to be closely monitored.
Dental Health: Effects on Dental Treatment
No significant effects or complications reported
Dental Health: Vasoconstrictor/Local Anesthetic Precautions
No information available to require special precautions
Mental Health: Effects on Mental Status
May cause dizziness
Mental Health: Effects on Psychiatric Treatment
May cause agranulocytosis; use caution with clozapine and carbamazepine; may decrease lithium clearance resulting in an increase in serum lithium levels and potential lithium toxicity, however, this is much more common and significant with the thiazide diuretics; monitor serum lithium levels; concurrent use with chloral hydrate may produce hot flashes and hypertension
Nursing: Physical Assessment/Monitoring
Assess for allergy to sulfonylurea before beginning therapy. Monitor for dehydration, electrolyte imbalance, and postural hypotension on a regular basis during therapy.
Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Injection, solution: 10 mg/mL (2 mL, 5 mL)
Tablet, oral: 5 mg, 10 mg, 20 mg, 100 mg
Demadex®: 5 mg, 10 mg, 20 mg, 100 mg [scored]
Pricing: U.S. (www.drugstore.com)
Tablets (Demadex)
10 mg (30): $43.69
20 mg (30): $55.99
100 mg (30): $160.99
Tablets (Torsemide)
5 mg (30): $18.99
10 mg (30): $20.99
10 mg (30): $29.99
20 mg (30): $22.99
100 mg (30): $89.99
References
Bard RL, Bleske BE, and Nicklas JM, “Food: An Unrecognized Source of Loop Diuretic Resistance,” Pharmacotherapy, 2004, 24(5):630-7.
Chobanian AV, Bakris GL, Black HR, et al, “The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure: The JNC 7 Report,” JAMA, 2003, 289(19):2560-71.
Hariman RJ, Bremner S, Louie EK, et al, “Dose-Response Study of Intravenous Torsemide in Congestive Heart Failure,” Am Heart J, 1994, 128(2):352-7.
Hunt SA, Abraham WT, Chin MH, et al, “2009 Focused Update Incorporated into the ACC/AHA 2005 Guidelines for the Diagnosis and Management of Heart Failure in Adults: A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines Developed in Collaboration With the International Society for Heart and Lung Transplantation,” J Am Coll Cardiol, 2009, 53(15):e1-e90.
Lindenfeld J, Albert NM, Boehmer JP, et al, “HFSA 2010 Comprehensive Heart Failure Practice Guideline,” J Card Fail, 2010, 16(6):e1-194.
International Brand Names
Lexi-Comp.com
Last full review/revision May 2011
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