Benazepril
Clinical Particulars
Benazepril is a prodrug that inhibits the conversion of angiotensin-I to angiotensin-II by inhibiting angiotensin-converting enzyme (ACE) after being hydrolysed in the liver to benazeprilat (Booth, 2011; Maddison, 2008; Plumb, 2024).
Pharmacokinetics
Mechanism of Action
Benazeprilat is a highly potent and selective inhibitor of ACE, thus preventing the conversion of inactive angiotensin I to active angiotensin II and reducing aldosterone synthesis. Benazeprilat blocks effects mediated by angiotensin II and aldosterone, including vasoconstriction of both arteries and veins, sodium and water retention by the kidney, and remodelling effects (including pathological cardiac hypertrophy and degenerative renal changes).
Arterial and venous vasodilation - decrease preload - decrease afterload: Veno- and artery dilatation and decreased salt and water retention (reduced aldosterone production). Renal vasoconstrictive activity and stimulation of secretion of aldosterone by the adrenal cortex.
Reduced glomerular filtration pressure: Proteinuria may be reduced.
Mechanism
ACE inhibitors inhibit the conversion of angiotensin-I to angiotensin-II, resulting in veno- and artery dilatation and decreased salt and water retention (through reduced aldosterone production). Efferent renal arteriolar dilatation results in a reduced glomerular filtration pressure.
The enzymatic cascade by which angiotensin-II is produced consists of renin, which cleaves angiotensinogen to form the decapeptide angiotensin-I. Angiotensin-I is then cleaved by angiotensin-converting enzyme (ACE) to produce angiotensin-II, the physiologically active component of the system.
Systemic actions of angiotensin-II are mainly hypertensive. Bradykinin, an endogenous vasodilator peptide, is also metabolised by ACE. Inhibition of ACE contributes to vasodilatation by decreasing the angiotensin-II production and inhibiting the bradykinin catabolism.
Angiotensin-II also increases water volume through sodium (via aldosterone) and water (via anti-diuretic hormone) retention. In renal pathophysiological conditions, it is also responsible for the growth and profibrogenic actions, cell proliferation, production of cytokines and extracellular matrix proteins and renal inflammatory cell infiltration.
Applications
Congestive heart failure
Protein-losing glomerulopathy
Hypertension
Ischaemic stroke
Pharmacodynamics
Metabolism
Benazepril hydrochloride is a pro-drug hydrolysed in vivo to benazeprilat, which inhibits angiotensin-converting enzyme (ACE), thus preventing the conversion of inactive angiotensin-I into active angiotensin-II.
Benazepril reduces all effects mediated by angiotensin-II, including vasoconstriction of arteries and veins and kidney retention of sodium and water.
Elimination
Benazepril and benazeprilat are cleared predominantly by renal excretion in healthy subjects with normal renal function.
Nonrenal (i.e., biliary) excretion accounts for approximately 11%-12% of benazeprilat excretion in healthy subjects.
Precautions
Adverse Effects
Severe CHF: Monitor for progressive azotaemia, especially where aggressive diuresis has recently occurred. Avoid use in cardiac output failure due, for example, to aortic stenosis.
GI Distress: Typically, anorexia, vomiting, and diarrhoea.
Hypotension: Animals may experience excessive hypotension, and fatigue, lethargy, ataxia, and incoordination may be observed.
Azotaemia: Renal dysfunction, azotaemia and hyperkalemia may occur. Plasma creatinine concentration may increase at the start of therapy in patients with CKD or dehydration.
Contraindications
AKI: Avoid use in animals at risk of azotaemia as use may decrease GFR and worsen azotemia
Hypersensitivity: Avoid use in patients with known hypersensitivity to ACE inhibitors.
Hyponatremia or Sodium Depletion: Avoid use.
Hypotension: Avoid use in animals with or at risk of hypotension.
Hypovolemia: Avoid use.
Coronary or Cerebrovascular Insufficiency: Avoid use.
Pre-existing Hematologic Abnormalities: Avoid use.
SLE or Collagen Vascular Disease: Avoid use (e.g., systemic lupus erythematosus [SLE]).
Reproductive Safety
Pregnancy: Avoid use. Benazepril crosses the placenta. Embryotoxic effects (foetal urinary tract malformation) were seen in trials with laboratory animals (rats) at maternally non-toxic doses (SPC data).
Lactation: Benazepril is not expected to cause adverse effects in an infant being nursed. However, in some countries, its use is contraindicated during pregnancy and lactation (SPC data).
Male Fertility: No data located.
Female Fertility: Avoid use. Benazepril reduced ovary/oviduct weights in cats when administered daily at 10 mg/kg body weight for 52 weeks (SPC data).
Neonates: Benazepril is not expected to cause adverse effects in an infant being nursed (SPC data).
Potentially Significant Interactions
Anti-hypertensive agents: e.g. calcium channel blockers, β-blockers or diuretics), anaesthetics or sedatives may lead to additive hypotensive effects (SPC data).
NSAIDs: e.g., carprofen, meloxicam, robenacoxib): can lead to reduced anti-hypertensive efficacy or impaired renal function (SPC data).
Availability
UK Formulations
Oral Forms: 2.5 mg, 5mg and 20mg Tablets
UK Availability: Sole agent or combined with other diuretics such as hydrochlorothiazide.
Identifiers
Systematic IUPAC Name: 2-[(3S)-3-[[(2S)-1-ethoxy-1-oxo-4-phenylbutan-2-yl]amino]-2-oxo-4,5-dihydro-3H-1-benzazepin-1-yl]acetic acid
Formula: C24H28N2O5
Pharmacotherapeutic group: Cardiovascular system, ACE Inhibitor,
ATC code: C09AA07 (WHO)
ATC vet code: QC09AA07 (WHO)
Evidence Base
Acierno, M.J., Brown, S., Coleman, A.E., Jepson, R.E., Papich, M., Stepien, R.L., Syme, H.M., 2018a. ACVIM consensus statement: Guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats. J Vet Intern Med 32, 1803–1822. https://doi.org/10.1111/jvim.15331
Acierno, M.J., Brown, S., Coleman, A.E., Jepson, R.E., Papich, M., Stepien, R.L., Syme, H.M., 2018b. ACVIM consensus statement: Guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats. Journal of Veterinary Internal Medicine 32, 1803–1822. https://doi.org/10.1111/jvim.15331
Adin, D., Atkins, C., Wallace, G., Klein, A., 2021. Effect of spironolactone and benazepril on furosemide‐induced diuresis and renin‐angiotensin‐aldosterone system activation in normal dogs. J Vet Intern Med 35, 1245–1254. https://doi.org/10.1111/jvim.16097
Arixil Vet 5 mg Film-coated Tablet for Dogs and Cats [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A009988 (accessed 1.1.24).
Arixil Vet 20 mg Film-coated Tablet for Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A009989 (accessed 1.1.24).
Banacep Vet 5 mg Film-coated Tablet for Dogs and Cats [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A006998 (accessed 1.1.24).
Banacep Vet 20 mg Film-coated Tablet for Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A008086 (accessed 1.1.24).
Benazecare Flavour 5 mg Tablets for Dogs and Cats [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A006679 (accessed 1.1.24).
Benazecare Flavour 20 mg Tablets for Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A006680 (accessed 1.1.24).
BenazeVet 2.5 mg Tablets for Cats and Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A010811 (accessed 1.1.24).
BenazeVet 5 mg Tablets for Cats and Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A010803 (accessed 1.1.24).
BenazeVet 20 mg Tablets for Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A010804 (accessed 1.1.24).
BENCH (BENazepril in Canine Heart disease) Study Group, 1999. The effect of benazepril on survival times and clinical signs of dogs with congestive heart failure: Results of a multicenter, prospective, randomized, double-blinded, placebo-controlled, long-term clinical trial. J Vet Cardiol 1, 7–18. https://doi.org/10.1016/S1760-2734(06)70025-X
Benefortin Flavour 2.5 mg Tablets for Cats and Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A008272 (accessed 1.1.24).
Benefortin Flavour 5 mg Tablets for Cats and Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A008273 (accessed 1.1.24).
Benefortin Flavour 20 mg Tablets for Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A008274 (accessed 1.1.24).
Booth, D., 2011. Small Animal Clinical Pharmacology and Therapeutics - 2nd Edition [WWW Document]. URL https://shop.elsevier.com/books/small-animal-clinical-pharmacology-and-therapeutics/boothe/978-0-7216-0555-5 (accessed 1.24.24).
Brennan, M., Stavisky, J., 2015. Benazepril in dogs with asymptomatic mitral valve disease. Veterinary Record 177, 392–392. https://doi.org/10.1136/vr.h4110
Cardalis 2.5 mg/20 mg Chewable Tablets for Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A008282 (accessed 1.1.24a).
Cardalis 2.5 mg/20 mg Chewable Tablets for Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A008282 (accessed 1.1.24b).
Cardalis 5 mg/40 mg Chewable Tablets for Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A008569 (accessed 1.1.24).
Cardalis 10 mg/80 mg Chewable Tablets for Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A008570 (accessed 1.1.24).
Chitty, J., 2015. Cardiovascular disease in rabbits. Companion Animal 20, 74–78. https://doi.org/10.12968/coan.2015.20.2.74
Coffman, M., Guillot, E., Blondel, T., Garelli-Paar, C., Feng, S., Heartsill, S., Atkins, C.E., 2021. Clinical efficacy of a benazepril and spironolactone combination in dogs with congestive heart failure due to myxomatous mitral valve disease: The BEnazepril Spironolactone STudy (BESST). J Vet Intern Med 35, 1673–1687. https://doi.org/10.1111/jvim.16155
Fortekor 2.5 mg Tablets for Cats and Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A005871 (accessed 1.1.24).
Fortekor Flavour 5 mg Tablets for Cats and Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A007625 (accessed 1.1.24).
Fortekor Flavour 20 mg Tablets for Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A007630 (accessed 1.1.24).
Fortekor Plus 5mg/10mg Tablets [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A009422 (accessed 1.1.24).
Häggström, J., Boswood, A., O’Grady, M., Jöns, O., Smith, S., Swift, S., Borgarelli, M., Gavaghan, B., Kresken, J.-G., Patteson, M., Åblad, B., Bussadori, C. m., Glaus, T., Kovačević, A., Rapp, M., Santilli, R. a., Tidholm, A., Eriksson, A., Belanger, M. c., Deinert, M., Little, C. j. l., Kvart, C., French, A., Rønn-Landbo, M., Wess, G., Eggertsdottir, A., Lynne O’Sullivan, M., Schneider, M., Lombard, C. w., Dukes-McEwan, J., Willis, R., Louvet, A., DiFruscia, R., 2013a. Longitudinal Analysis of Quality of Life, Clinical, Radiographic, Echocardiographic, and Laboratory Variables in Dogs with Myxomatous Mitral Valve Disease Receiving Pimobendan or Benazepril: The QUEST Study. Journal of Veterinary Internal Medicine 27, 1441–1451. https://doi.org/10.1111/jvim.12181
Häggström, J., Boswood, A., O’Grady, M., Jöns, O., Smith, S., Swift, S., Borgarelli, M., Gavaghan, B., Kresken, J.-G., Patteson, M., Ablad, B., Bussadori, C.M., Glaus, T., Kovacević, A., Rapp, M., Santilli, R.A., Tidholm, A., Eriksson, A., Belanger, M.C., Deinert, M., Little, C.J.L., Kvart, C., French, A., Rønn-Landbo, M., Wess, G., Eggertsdottir, A.V., O’Sullivan, M.L., Schneider, M., Lombard, C.W., Dukes-McEwan, J., Willis, R., Louvet, A., DiFruscia, R., 2008. Effect of pimobendan or benazepril hydrochloride on survival times in dogs with congestive heart failure caused by naturally occurring myxomatous mitral valve disease: the QUEST study. J Vet Intern Med 22, 1124–1135. https://doi.org/10.1111/j.1939-1676.2008.0150.x
Häggström, J., Lord, P.F., Höglund, K., Ljungvall, I., Jöns, O., Kvart, C., Hansson, K., 2013b. Short-term hemodynamic and neuroendocrine effects of pimobendan and benazapril in dogs with myxomatous mitral valve disease and congestive heart failure. J Vet Intern Med 27, 1452–1462. https://doi.org/10.1111/jvim.12217
Keene, B.W., Atkins, C.E., Bonagura, J.D., Fox, P.R., Häggström, J., Fuentes, V.L., Oyama, M.A., Rush, J.E., Stepien, R., Uechi, M., 2019. ACVIM consensus guidelines for the diagnosis and treatment of myxomatous mitral valve disease in dogs. J Vet Intern Med 33, 1127–1140. https://doi.org/10.1111/jvim.15488
Kelapril 5 mg, Film-coated Tablets for Dogs and Cats [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A008293 (accessed 1.1.24).
Kelapril 20 mg, Film-coated Tablets for Dogs [WWW Document], n.d. URL https://www.vmd.defra.gov.uk/productinformationdatabase/product/A008294 (accessed 1.1.24).
King, J.N., Font, A., Rousselot, J.-F., Ash, R.A., Bonfanti, U., Brovida, C., Crowe, I.D., Lanore, D., Pechereau, D., Seewald, W., Strehlau, G., 2017. Effects of Benazepril on Survival of Dogs with Chronic Kidney Disease: A Multicenter, Randomized, Blinded, Placebo-Controlled Clinical Trial. J Vet Intern Med 31, 1113–1122. https://doi.org/10.1111/jvim.14726
King, J.N., Hirakawa, A., Sonobe, J., Otaki, H., Sakakibara, N., Seewald, W., Forster, S., 2018. Evaluation of a fixed-dose combination of benazepril and pimobendan in dogs with congestive heart failure: a randomized non-inferiority clinical trial. J Vet Sci 19, 117–128. https://doi.org/10.4142/jvs.2018.19.1.117
Kittleson, M., Rishniw, M., Pion, P., Kass, P., 2009. Effect of benazepril on survival and cardiac events in dogs with asymptomatic mitral valve disease: A retrospective study of 141 cases. J Vet Intern Med 23, 953–954; author reply 955-956. https://doi.org/10.1111/j.1939-1676.2009.0361.x
Kortum, A.J., Bazelle, J., Gomez Selgas, A., Kent, A.C.C., Williams, T.L., Herrtage, M.E., 2021. Clinical findings and outcome following medical treatment in dogs with idiopathic renal haematuria: 41 cases (2001–2018). Journal of Small Animal Practice 62, 850–860. https://doi.org/10.1111/jsap.13352
Lantis, A.C., Ames, M.K., Atkins, C.E., DeFrancesco, T.C., Keene, B.W., Werre, S.R., 2015. Aldosterone breakthrough with benazepril in furosemide-activated renin-angiotensin-aldosterone system in normal dogs. Journal of Veterinary Pharmacology and Therapeutics 38, 65–73. https://doi.org/10.1111/jvp.12154
Li, J., Wanchun, C., 1997. Benazepril on tissue angiotensin-converting enzyme and cellular proliferation in restenosis after experimental angioplasty. J Cardiovasc Pharmacol 30, 790–797. https://doi.org/10.1097/00005344-199712000-00014
Lombard, C.W., Jöns, O., Bussadori, C.M., 2006. Clinical efficacy of pimobendan versus benazepril for the treatment of acquired atrioventricular valvular disease in dogs. J Am Anim Hosp Assoc 42, 249–261. https://doi.org/10.5326/0420249
Maddison, G., 2008. Small Animal Clinical Pharmacology E-Book: 2nd edition | Edited by Jill E. Maddison | ISBN: 9780702037252 [WWW Document]. Elsevier Asia Bookstore. URL https://www.asia.elsevierhealth.com/small-animal-clinical-pharmacology-e-book-9780702037252.html (accessed 1.23.24).
Müller, K., Mancinelli, E., 2022. Cardiology in Rabbits and Rodents–Common Cardiac Diseases, Therapeutic Options, and Limitations. Veterinary Clinics of North America: Exotic Animal Practice, Cardiology 25, 525–540. https://doi.org/10.1016/j.cvex.2022.01.006
O’Grady, M.R., O’Sullivan, M.L., Minors, S.L., Horne, R., 2009. Efficacy of benazepril hydrochloride to delay the progression of occult dilated cardiomyopathy in Doberman Pinschers. J Vet Intern Med 23, 977–983. https://doi.org/10.1111/j.1939-1676.2009.0346.x
Ozawa, S., Guzman, D.S.-M., Keel, K., Gunther-Harrington, C., 2021. Clinical and pathological findings in rabbits with cardiovascular disease: 59 cases (2001–2018). Journal of the American Veterinary Medical Association 259, 764–776. https://doi.org/10.2460/javma.259.7.764
Panteri, A., Kukk, A., Desevaux, C., Seewald, W., King, J.N., 2017. Effect of benazepril and robenacoxib and their combination on glomerular filtration rate in dogs. Journal of Veterinary Pharmacology and Therapeutics 40, 44–56. https://doi.org/10.1111/jvp.12325
Pariaut, R., 2009. Cardiovascular Physiology and Diseases of the Rabbit. Veterinary Clinics of North America: Exotic Animal Practice, Cardiology 12, 135–144. https://doi.org/10.1016/j.cvex.2008.08.004
Paul-Murphy, J., Ramer, J.C., 1998. Urgent care of the pet rabbit. Vet Clin North Am Exot Anim Pract 1, 127–152, vi–vii. https://doi.org/10.1016/s1094-9194(17)30158-5
Plumb, 2024. Benazepril [WWW Document]. URL https://app.plumbs.com/drug/PGVZkcnorQPROD?source=search&searchQuery=benaze (accessed 1.24.24).
Porciello, F., Rishniw, M., Ljungvall, I., Ferasin, L., Haggstrom, J., Ohad, D.G., 2016. Sleeping and resting respiratory rates in dogs and cats with medically-controlled left-sided congestive heart failure. The Veterinary Journal 207, 164–168. https://doi.org/10.1016/j.tvjl.2015.08.017
Quesenberry, K.E. (Ed.), 2021. Ferrets, rabbits, and rodents: clinical medicine and surgery, Fourth edition. ed. Elsevier, St. Louis, Missouri.
Regulski, M., Regulska, K., Stanisz, B.J., Murias, M., Gieremek, P., Wzgarda, A., Niznik, B., 2015. Chemistry and pharmacology of Angiotensin-converting enzyme inhibitors. Curr Pharm Des 21, 1764–1775. https://doi.org/10.2174/1381612820666141112160013
Reusch, B., 2005. Investigation and management of cardiovascular disease in rabbits. In Practice 27, 418–425. https://doi.org/10.1136/inpract.27.8.418
Rishniw, M., 2020. Angiotensin-Converting Enzyme Inhibitors and Cardiac Disease: Have They Had Their Day? Advances in Small Animal Medicine and Surgery 33, 1–3. https://doi.org/10.1016/j.asams.2020.01.009
Sheinberg, G., Romero, C., Heredia, R., Capulin, M., Yarto, E., Carpio, J., 2017. Use of oral fluralaner for the treatment of Psoroptes cuniculi in 15 naturally infested rabbits. Vet Dermatol 28, 393-e91. https://doi.org/10.1111/vde.12429
Suzuki, S., Fukushima, R., Ishikawa, T., Yamamoto, Y., Hamabe, L., Kim, S., Yoshiyuki, R., Machida, N., Tanaka, R., 2012. Comparative effects of amlodipine and benazepril on Left Atrial Pressure in Dogs with experimentally-induced Mitral Valve Regurgitation. BMC Vet Res 8, 166. https://doi.org/10.1186/1746-6148-8-166
Toutain, P.L., Lefèbvre, H.P., 2004. Pharmacokinetics and pharmacokinetic/pharmacodynamic relationships for angiotensin-converting enzyme inhibitors. Journal of Veterinary Pharmacology and Therapeutics 27, 515–525. https://doi.org/10.1111/j.1365-2885.2004.00601.x
Varga-Smith, M., 2022. Textbook of Rabbit Medicine - 9780702084034 | Elsevier Health [WWW Document]. Elsevier UK. URL https://www.uk.elsevierhealth.com/textbook-of-rabbit-medicine-9780702084034.html (accessed 1.23.24).
Ward, J.L., Chou, Y.-Y., Yuan, L., Dorman, K.S., Mochel, J.P., 2021. Retrospective evaluation of a dose-dependent effect of angiotensin-converting enzyme inhibitors on long-term outcome in dogs with cardiac disease. J Vet Intern Med 35, 2102–2111. https://doi.org/10.1111/jvim.16236
Yamamoto, S., Takemori, E., Hasegawa, Y., Kuroda, K., Nakao, K., Inukai, T., Sakonjyo, H., Nishimura, T., Nishimori, T., 1991. General pharmacology of the novel angiotensin converting enzyme inhibitor benazepril hydrochloride. Effects on cardiovascular, visceral and renal functions and on hemodynamics. Arzneimittelforschung 41, 913–923.
Zatelli, A., Roura, X., D’Ippolito, P., Berlanda, M., Zini, E., 2016. The effect of renal diet in association with enalapril or benazepril on proteinuria in dogs with proteinuric chronic kidney disease. Open Vet J 6, 121–127. https://doi.org/10.4314/ovj.v6i2.8