Furosemide Explained

Watchedfields:changed
Verifiedrevid:461114978
Tradename:Lasix, Furoscix, others
Dailymedid:Furosemide
Pregnancy Au:C
Routes Of Administration:oral, intravenous, intramuscular, subcutaneous
Atc Prefix:C03
Atc Suffix:CA01
Legal Au:S4
Legal Uk:POM
Legal Us:Rx-only
Legal Us Comment:[1] [2]
Legal Status:Rx-only
Bioavailability:43–69%
Protein Bound:91–99%
Metabolism:liver and kidney glucuronidation
Onset:30 to 60 min (PO), 5 min (IV)
Elimination Half-Life:up to 100 minutes
Excretion:Kidneys (66%), bile (33%)
Cas Number:54-31-9
Pubchem:3440
Drugbank:DB00695
Chemspiderid:3322
Unii:7LXU5N7ZO5
Kegg:D00331
Chebi:47426
Chembl:35
Synonyms:Furosemide
Iupac Name:4-Chloro-2-[(furan-2-ylmethyl)amino]-5-sulfamoylbenzoic acid
C:12
H:11
Cl:1
N:2
O:5
S:1
Smiles:o1cccc1CNc(cc2Cl)c(C(=O)O)cc2S(=O)(=O)N
Stdinchi:1S/C12H11ClN2O5S/c13-9-5-10(15-6-7-2-1-3-20-7)8(12(16)17)4-11(9)21(14,18)19/h1-5,15H,6H2,(H,16,17)(H2,14,18,19)
Stdinchikey:ZZUFCTLCJUWOSV-UHFFFAOYSA-N

Furosemide is a loop diuretic medication used to treat edema due to heart failure, liver scarring, or kidney disease.[3] It has had many trade names including Discoid, Frusemide, Lasix and Uremide. Furosemide may also be used for the treatment of high blood pressure.[3] It can be taken intravenously or orally.[3] When given intravenously, furosemide typically takes effect within five minutes; when taken orally, it typically metabolizes within an hour.[3]

Common side effects include orthostatic hypotension (decrease in blood pressure while standing, and associated lightheadedness), tinnitus (ringing in the ears), and photosensitivity (sensitivity to light).[3] Potentially serious side effects include electrolyte abnormalities, low blood pressure, and hearing loss.[3] It is recommended that serum electrolytes (especially potassium), serum CO2, creatinine, BUN levels, and liver and kidney functioning be monitored in patients taking furosemide. It is also recommended to be alert for the occurrence of any potential blood dyscrasias.[3] Furosemide is a type of loop diuretic that works by decreasing the reabsorption of sodium by the kidneys.[3] Common side effects of furosemide injection include hypokalemia (low potassium level), hypotension (low blood pressure), and dizziness.[4]

Furosemide was patented in 1959 and approved for medical use in 1964.[5] It is on the World Health Organization's List of Essential Medicines.[6] In the United States, it is available as a generic medication.[3] In 2021, it was the 21st most commonly prescribed medication in the United States, with more than 26million prescriptions.[7] [8] In 2020/21 it was the twentieth most prescribed medication in England.[9] It is on the World Anti-Doping Agency's banned drug list due to concerns that it may mask other drugs.[10] It has also been used in race horses for the treatment and prevention of exercise-induced pulmonary hemorrhage.[11] [12]

Medical uses

Furosemide is primarily used for the treatment of edema, but also in some cases of hypertension (where there is also kidney or heart impairment).[13] It is often viewed as a first-line agent in most people with edema caused by congestive heart failure because of its anti-vasoconstrictor and diuretic effects.[3] [14] Compared with furosemide, however, torasemide (aka "torsemide") has been demonstrated to show improvements to heart failure symptoms, possibly lowering the rates of rehospitalisation associated with heart failure, with no difference in risk of death. [15] [16] [17] Torsemide may also be safer than furosemide.[18] [19] Providing self-administered subcutaneous furosemide has been found to reduce hospital admissions in people with heart failure, resulting in significant savings in healthcare costs.[20] [21]

Furosemide is also used for liver cirrhosis, kidney impairment, nephrotic syndrome, in adjunct therapy for swelling of the brain or lungs where rapid diuresis is required (IV injection), and in the management of severe hypercalcemia in combination with adequate rehydration.[22]

Kidney disease

In chronic kidney diseases with hypoalbuminemia, furosemide is used along with albumin to increase diuresis.[23] It is also used along with albumin in nephrotic syndrome to reduce edema.[24]

Other information

Furosemide is mainly excreted by tubular secretion in the kidney. In kidney impairment, clearance is reduced, increasing the risk of adverse effects.[3] Lower initial doses are recommended in older patients (to minimize side-effects) and high doses may be needed in kidney failure.[25] It can also cause kidney damage; this is mainly by loss of excessive fluid (i.e., dehydration), and is usually reversible.

Furosemide acts within 1 hour of oral administration (after IV injection, the peak effect is within 30 minutes). Diuresis is usually complete within 6–8 hours of oral administration, but there is significant variation between individuals.[26]

Adverse effects

Furosemide also can lead to gout caused by hyperuricemia. Hyperglycemia is also a common side effect.[27] [28] [29]

The tendency, as for all loop diuretics, to cause low serum potassium concentration (hypokalemia) has given rise to combination products, either with potassium or with the potassium-sparing diuretic amiloride (Co-amilofruse). Other electrolyte abnormalities that can result from furosemide use include hyponatremia, hypochloremia, hypomagnesemia, and hypocalcemia.[30]

In the treatment of heart failure, many studies have shown that the long-term use of furosemide can cause varying degrees of thiamine deficiency, so thiamine supplementation is also suggested.[31]

Furosemide is a known ototoxic agent generally causing transient hearing loss but can be permanent. Reported cases of furosemide induced hearing loss appeared to be associated with rapid intravenous administration, high dosages, concomitant renal disease and coadministration with other ototoxic medication.[32] [33] However, a recently reported longitudinal study showed that participants treated with loop diuretics over 10 years were 40% more likely to develop hearing loss and 33% more likely of progressive hearing loss compared to participants who did not use loop diuretics.[34] This suggests the long-term consequences of loop diuretics on hearing could be a more significant than previously thought and further research is required in this area.  

Other precautions include: nephrotoxicity, sulfonamide (sulfa) allergy, and increases free thyroid hormone effects with large doses.[35]

Interactions

Furosemide has potential interactions with these medications:[36]

Potentially hazardous interactions with other drugs:

Mechanism of action

See main article: Loop diuretic. Furosemide, like other loop diuretics, acts by inhibiting the luminal Na-K-Cl cotransporter in the thick ascending limb of the loop of Henle, by binding to the Na-K-2Cl transporter, thus causing more sodium, chloride, and potassium to be excreted in the urine.[37]

The action on the distal tubules is independent of any inhibitory effect on carbonic anhydrase or aldosterone; it also abolishes the corticomedullary osmotic gradient and blocks negative, as well as positive, free water clearance. Because of the large NaCl absorptive capacity of the loop of Henle, diuresis is not limited by development of acidosis, as it is with the carbonic anhydrase inhibitors.

Additionally, furosemide is a noncompetitive subtype-specific blocker of GABA-A receptors.[38] [39] [40] Furosemide has been reported to reversibly antagonize GABA-evoked currents of α6β2γ2 receptors at μM concentrations, but not α1β2γ2 receptors.[38] [40] During development, the α6β2γ2 receptor increases in expression in cerebellar granule neurons, corresponding to increased sensitivity to furosemide.[39]

Pharmacokinetics

The pharmacokinetics of furosemide are apparently not significantly altered by food.[50]

No direct relationship has been found between furosemide concentration in the plasma and furosemide efficacy. Efficacy depends upon the concentration of furosemide in urine.[26]

Names

Furosemide is the INN and BAN.[51] The previous BAN was frusemide.

Brand names under which furosemide is marketed include: Aisemide, Apo-Furosemide, Beronald, Desdemin, Discoid, Diural, Diurapid, Dryptal, Durafurid, Edemid, Errolon, Eutensin, Farsiretic, Flusapex, Frudix, Frusemide, Frusetic, Frusid, Fulsix, Fuluvamide, Furantril, Furesis, Furix, Furo-Puren, Furon, Furosedon, Fusid.frusone, Hydro-rapid, Impugan, Katlex, Lasilix, Lasix, Lodix, Lowpston, Macasirool, Mirfat, Nicorol, Odemase, Oedemex, Profemin, Rosemide, Rusyde, Salix, Seguril, Teva-Furosemide, Trofurit, Uremide, and Urex.

Veterinary uses

The diuretic effects are put to use most commonly in horses to prevent bleeding during a race. In the United States of America, pursuant to the racing rules of most states, horses that bleed from the nostrils (exercise-induced pulmonary hemorrhage) three times are permanently barred from racing. Sometime in the early 1970s, furosemide's ability to prevent, or at least greatly reduce, the incidence of bleeding by horses during races was discovered accidentally. Clinical trials followed, and by decade's end, racing commissions in some states in the USA began legalizing its use on race horses. In 1995, New York became the last state in the United States to approve such use, after years of refusing to consider doing so.[52] Some states allow its use for all racehorses; some allow it only for confirmed "bleeders". Its use for this purpose is still prohibited in many other countries.

Furosemide is also used in horses for pulmonary edema, congestive heart failure (in combination with other drugs), and allergic reactions. Although it increases circulation to the kidneys, it does not help kidney function, and is not recommended for kidney disease.[53]

It is also used to treat congestive heart failure (pulmonary edema, pleural effusion, and/or ascites) in cats and dogs.[54] It can also be used in an attempt to promote urine production in anuric or oliguric acute kidney failure.

Horses

Furosemide is injected either intramuscularly or intravenously, usually 0.5-1.0 mg/kg twice/day, although less before a horse is raced. As with many diuretics, it can cause dehydration and electrolyte imbalance, including loss of potassium, calcium, sodium, and magnesium. Excessive use of furosemide will most likely lead to a metabolic alkalosis due to hypochloremia and hypokalemia. The drug should, therefore, not be used in horses that are dehydrated or experiencing kidney failure. It should be used with caution in horses with liver problems or electrolyte abnormalities. Overdose may lead to dehydration, change in drinking patterns and urination, seizures, gastrointestinal problems, kidney damage, lethargy, collapse, and coma.

Furosemide should be used with caution when combined with corticosteroids (as this increases the risk of electrolyte imbalance), aminoglycoside antibiotics (increases risk of kidney or ear damage), and trimethoprim sulfa (causes decreased platelet count). It may also cause interactions with anesthetics, so its use should be related to the veterinarian if the animal is going into surgery, and it decreases the kidneys' ability to excrete aspirin, so dosages will need to be adjusted if combined with that drug.

Furosemide may increase the risk of digoxin toxicity due to hypokalemia.

The drug is best not used during pregnancy or in a lactating mare, as it has been shown to be passed through the placenta and milk in studies with other species. It should not be used in horses with pituitary pars intermedia dysfunction (Cushings).

Furosemide is detectable in urine 36–72 hours following injection. Its use is restricted by most equestrian organizations.

In April 2019, it was announced that Lasix would be banned from use at US racetracks within 24 hours of a horse racing starting in 2021.[55]

Further reading

External links

Notes and References

  1. Web site: Lasix- furosemide tablet . DailyMed . 26 January 2021 . 18 November 2022.
  2. Web site: Furoscix- furosemide injection 80 mg/ 10 ml injection . DailyMed . 21 October 2022 . 18 November 2022.
  3. Web site: Furosemide. The American Society of Health-System Pharmacists. 23 October 2015. live. https://web.archive.org/web/20151119161939/http://www.drugs.com/monograph/furosemide.html. 19 November 2015.
  4. Coronavirus (COVID-19) Update: December 22, 2020 . U.S. Food and Drug Administration . 22 December 2020 . 22 December 2020.
  5. Book: Fischer J, Ganellin CR . Analogue-based Drug Discovery . 2006 . John Wiley & Sons . 9783527607495 . 458 . en.
  6. Book: ((World Health Organization)) . World Health Organization model list of essential medicines: 21st list 2019 . 2019 . 10665/325771 . World Health Organization . World Health Organization . Geneva . WHO/MVP/EMP/IAU/2019.06. License: CC BY-NC-SA 3.0 IGO . free .
  7. Web site: The Top 300 of 2021 . ClinCalc . 14 January 2024 . 15 January 2024 . https://web.archive.org/web/20240115223848/https://clincalc.com/DrugStats/Top300Drugs.aspx . live .
  8. Web site: Furosemide - Drug Usage Statistics . ClinCalc . 14 January 2024.
  9. Web site: PCA England . 8 August 2022 . nhsbsa-opendata.s3.eu-west-2.amazonaws.com.
  10. Web site: WORLD ANTI-DOPING CODE INTERNATIONAL STANDARD PROHIBITED LIST 2022. 27 July 2022. 12. 2022. live. https://web.archive.org/web/20220710154918/https://www.wada-ama.org/sites/default/files/resources/files/2022list_final_en.pdf. 10 July 2022.
  11. Sullivan S, Hinchcliff K . Update on exercise-induced pulmonary hemorrhage . The Veterinary Clinics of North America. Equine Practice . 31 . 1 . 187–198 . April 2015 . 25770069 . 10.1016/j.cveq.2014.11.011 .
  12. Hinchcliff KW, Couetil LL, Knight PK, Morley PS, Robinson NE, Sweeney CR, van Erck E . Exercise induced pulmonary hemorrhage in horses: American College of Veterinary Internal Medicine consensus statement . Journal of Veterinary Internal Medicine . 29 . 3 . 743–758 . 2015 . 25996660 . 4895427 . 10.1111/jvim.12593 .
  13. Web site: Furosemide. The American Society of Health-System Pharmacists. 3 April 2011. live. https://web.archive.org/web/20110317080203/http://www.drugs.com/monograph/furosemide.html. 17 March 2011.
  14. Book: King KC, Goldstein S . Congestive Heart Failure And Pulmonary Edema . 2021 . http://www.ncbi.nlm.nih.gov/books/NBK554557/ . StatPearls. Treasure Island (FL) . StatPearls Publishing . 32119444 . 8 May 2021.
  15. Täger T, Fröhlich H, Seiz M, Katus HA, Frankenstein L . READY: relative efficacy of loop diuretics in patients with chronic systolic heart failure-a systematic review and network meta-analysis of randomised trials . Heart Failure Reviews . 24 . 4 . 461–472 . July 2019 . 30874955 . 10.1007/s10741-019-09771-8 . 77394851 .
  16. Miles JA, Hanumanthu BK, Patel K, Chen M, Siegel RM, Kokkinidis DG . Torsemide versus furosemide and intermediate-term outcomes in patients with heart failure: an updated meta-analysis . Journal of Cardiovascular Medicine . 20 . 6 . 379–388 . June 2019 . 30950982 . 10.2459/JCM.0000000000000794 . 96436158 .
  17. Abraham B, Megaly M, Sous M, Fransawyalkomos M, Saad M, Fraser R, Topf J, Goldsmith S, Simegn M, Bart B, Azzo Z, Mesiha N, Sharma R . Meta-Analysis Comparing Torsemide Versus Furosemide in Patients With Heart Failure . English . The American Journal of Cardiology . 125 . 1 . 92–99 . January 2020 . 31699358 . 10.1016/j.amjcard.2019.09.039 . 207937875 .
  18. Roush GC, Kaur R, Ernst ME . Diuretics: a review and update . Journal of Cardiovascular Pharmacology and Therapeutics . 19 . 1 . 5–13 . January 2014 . 24243991 . 10.1177/1074248413497257 . 21204143 .
  19. Buggey J, Mentz RJ, Pitt B, Eisenstein EL, Anstrom KJ, Velazquez EJ, O'Connor CM . A reappraisal of loop diuretic choice in heart failure patients . American Heart Journal . 169 . 3 . 323–333 . March 2015 . 25728721 . 4346710 . 10.1016/j.ahj.2014.12.009 .
  20. Dahiya G, Bensimhon D, Goodwin MM, Mohr JF, Alexy T . From Oral to Subcutaneous Furosemide: The Road to Novel Opportunities to Manage Congestion . Structural Heart . 6 . 4 . 100076 . August 2022 . 37288336 . 10.1016/j.shj.2022.100076 . 10242578 .
  21. Khan WJ, Arriola-Montenegro J, Mutschler MS, Bensimhon D, Halmosi R, Toth K, Alexy T . A novel opportunity to improve heart failure care: focusing on subcutaneous furosemide . Heart Failure Reviews . 28 . 6 . 1315–1323 . November 2023 . 37439967 . 10.1007/s10741-023-10331-4 . 259843357 .
  22. Book: Rossi S . Australian Medicines Handbook 2004 . 5th . 978-0-9578521-4-3 . 2004 . Australian Medicines Handbook Pty Ltd . Adelaide, S.A. .
  23. Kitsios GD, Mascari P, Ettunsi R, Gray AW . Co-administration of furosemide with albumin for overcoming diuretic resistance in patients with hypoalbuminemia: a meta-analysis . Journal of Critical Care . 29 . 2 . 253–259 . April 2014 . 24268626 . 10.1016/j.jcrc.2013.10.004 .
  24. Duffy M, Jain S, Harrell N, Kothari N, Reddi AS . Albumin and Furosemide Combination for Management of Edema in Nephrotic Syndrome: A Review of Clinical Studies . Cells . 4 . 4 . 622–630 . October 2015 . 26457719 . 4695849 . 10.3390/cells4040622 . free .
  25. Web site: British National Formulary . 9 November 2018.
  26. Ponto LL, Schoenwald RD . Furosemide (frusemide). A pharmacokinetic/pharmacodynamic review (Part I) . Clinical Pharmacokinetics . 18 . 5 . 381–408 . May 1990 . 2185908 . 10.2165/00003088-199018050-00004 . 32352501 .
  27. Li Q, Li X, Kwong JS, Chen H, Sun X, Tian H, Li S . Diagnosis and treatment for hyperuricaemia and gout: a protocol for a systematic review of clinical practice guidelines and consensus statements . BMJ Open . 7 . 6 . e014928 . June 2017 . 28645962 . 5623447 . 10.1136/bmjopen-2016-014928 .
  28. Li Q, Li X, Wang J, Liu H, Kwong JS, Chen H, Li L, Chung SC, Shah A, Chen Y, An Z, Sun X, Hemingway H, Tian H, Li S . Diagnosis and treatment for hyperuricemia and gout: a systematic review of clinical practice guidelines and consensus statements . BMJ Open . 9 . 8 . e026677 . August 2019 . 31446403 . 6720466 . 10.1136/bmjopen-2018-026677 .
  29. Han Y, Cao Y, Han X, Di H, Yin Y, Wu J, Zhang Y, Zeng X . Hyperuricemia and gout increased the risk of long-term mortality in patients with heart failure: insights from the National Health and Nutrition Examination Survey . J Transl Med . 21 . 1 . 463 . July 2023 . 37438830 . 10339518 . 10.1186/s12967-023-04307-z . free .
  30. Oh SW, Han SY . Loop Diuretics in Clinical Practice . Electrolyte & Blood Pressure . 13 . 1 . 17–21 . June 2015 . 26240596 . 4520883 . 10.5049/EBP.2015.13.1.17 .
  31. Katta N, Balla S, Alpert MA . Does Long-Term Furosemide Therapy Cause Thiamine Deficiency in Patients with Heart Failure? A Focused Review . The American Journal of Medicine . 129 . 7 . 753.e7–753.e11 . July 2016 . 26899752 . 10.1016/j.amjmed.2016.01.037 . free .
  32. Favrelière S, Delaunay P, Lebreton JP, Rouby F, Atzenhoffer M, Lafay-Chebassier C, Pérault-Pochat MC . Drug-induced hearing loss: a case/non-case study in the French pharmacovigilance database . Fundamental & Clinical Pharmacology . 34 . 3 . 397–407 . June 2020 . 31912913 . 10.1111/fcp.12533 . 210087413 .
  33. Gallagher KL, Jones JK . Furosemide-induced ototoxicity . Annals of Internal Medicine . 91 . 5 . 744–745 . November 1979 . 496112 . 10.7326/0003-4819-91-5-744 .
  34. Joo Y, Cruickshanks KJ, Klein BE, Klein R, Hong O, Wallhagen MI . The Contribution of Ototoxic Medications to Hearing Loss Among Older Adults . The Journals of Gerontology. Series A, Biological Sciences and Medical Sciences . 75 . 3 . 561–566 . February 2020 . 31282945 . 7328195 . 10.1093/gerona/glz166 . Newman A .
  35. Web site: UpToDate. www.uptodate.com. 6 November 2018.
  36. http://www.pdrhealth.com/drug_info/rxdrugprofiles/drugs/las1220.shtml Brand name:Lasix - Generic name: Furosemide
  37. Book: Dowd FJ, Johnson B, Mariotti A . Pharmacology and Therapeutics for Dentistry - E-Book. 3 September 2016. Elsevier Health Sciences. 9780323445955. 324–326. 4 November 2017.
  38. Korpi ER, Kuner T, Seeburg PH, Lüddens H . Selective antagonist for the cerebellar granule cell-specific gamma-aminobutyric acid type A receptor . Molecular Pharmacology . 47 . 2 . 283–289 . February 1995 . 7870036 .
  39. Tia S, Wang JF, Kotchabhakdi N, Vicini S . Developmental changes of inhibitory synaptic currents in cerebellar granule neurons: role of GABA(A) receptor alpha 6 subunit . The Journal of Neuroscience . 16 . 11 . 3630–3640 . June 1996 . 8642407 . 6578841 . 10.1523/JNEUROSCI.16-11-03630.1996 . free .
  40. Wafford KA, Thompson SA, Thomas D, Sikela J, Wilcox AS, Whiting PJ . Functional characterization of human gamma-aminobutyric acidA receptors containing the alpha 4 subunit . Molecular Pharmacology . 50 . 3 . 670–678 . September 1996 . 8794909 .
  41. AMA Department of Drugs: Drug Evaluations Subscription, American Medical Association, Chicago, IL, 1990.
  42. Knoben JE & Anderson PO (Eds): Handbook of Clinical Drug Data, 6th. Drug Intelligence Publications, Inc, Hamilton, IL, 1988.
  43. Web site: Product Information: Lasix(R), furosemide. . Aventis Pharmaceuticals, Bridgewater, NJ . 2004 . U.S. Food and Drug Administration .
  44. Book: Gilman AG, Rall TW, Nies AS, etal . Goodman and Gilman's The Pharmacological Basis of Therapeutics . 8th . Pergamon Press . New York, NY . 1990 .
  45. Kelly MR, Cutler RE, Forrey AW, Kimpel BM . Pharmacokinetics of orally administered furosemide . Clinical Pharmacology and Therapeutics . 15 . 2 . 178–186 . February 1974 . 4812154 . 10.1002/cpt1974152178 . 74223978 .
  46. Verbeeck RK, Patwardhan RV, Villeneuve JP, Wilkinson GR, Branch RA . Furosemide disposition in cirrhosis . Clinical Pharmacology and Therapeutics . 31 . 6 . 719–725 . June 1982 . 7075120 . 10.1038/clpt.1982.101 . 27659838 .
  47. Chaturvedi PR, O'Donnell JP, Nicholas JM, Shoenthal DR, Waters DH, Gwilt PR . Steady state absorption kinetics and pharmacodynamics of furosemide in congestive heart failure . International Journal of Clinical Pharmacology, Therapy, and Toxicology . 25 . 3 . 123–128 . March 1987 . 3557737 .
  48. Brater DC . Clinical pharmacology of loop diuretics . Drugs . 41 . Supplement 3 . 14–22 . 1991 . 1712712 . 10.2165/00003495-199100413-00004 . 41247401 .
  49. Haegeli L, Brunner-La Rocca HP, Wenk M, Pfisterer M, Drewe J, Krähenbühl S . Sublingual administration of furosemide: new application of an old drug . British Journal of Clinical Pharmacology . 64 . 6 . 804–809 . December 2007 . 17875188 . 2198789 . 10.1111/j.1365-2125.2007.03035.x .
  50. AHFS Drug Information 2004. McEvoy GK, ed. Furosemide. American Society of Health-System Pharmacists; 2004: 2260-4.
  51. Web site: Naming human medicines . 18 November 2009 . live . https://web.archive.org/web/20100427025454/http://www.mhra.gov.uk/Howweregulate/Medicines/Namingofmedicines/ChangestomedicinesnamesBANstorINNs/index.htm . 27 April 2010 .
  52. Web site: COMMENTARY : New York Buckles and Allows Lasix Use . . 22 January 2022 . 28 May 1995.
  53. Hinchcliff KW, Muir WW . Pharmacology of furosemide in the horse: a review . Journal of Veterinary Internal Medicine . 5 . 4 . 211–218 . January 2022 . 1941755 . 10.1111/j.1939-1676.1991.tb00951.x . free .
  54. Book: Kittleson M, Kienle R . Mark Kittleson . 1998 . Small Animal Cardiovascular Medicine . Mosby . registration . 978-0-8151-5140-1.
  55. Web site: U.S. Racetracks to ban race-day Lasix in 2021. 18 April 2019.