Imidapril

Oral
Essential hypertension

Patients with cardiac failure, cerebrovascular disease, or angina pectoris: Initially, 2.5 mg once daily. Close monitoring of the patient is required.

CrCl (mL/min)	Dosage
<10	Contraindicated.
10-29	Not recommended.
30-80	Initially, 2.5 mg once daily, then titrate the dose cautiously.

Initially, 2.5 mg once daily.

Should be taken on an empty stomach. Take 15 min before meals. However, when initiating therapy, 1st dose should be given at bedtime.

History of angioneurotic oedema related to previous ACE inhibitor therapy; hereditary or idiopathic angioedema. Patients undergoing haemodialysis with high-flux membranes (e.g. acrylonitrile methallyl sulfonate Na) and LDL apheresis with dextran sulfate cellulose. Renal failure with or without haemodialysis (CrCl <10 mL/min). Pregnancy. Concomitant use with aliskiren in patients with diabetes mellitus or renal impairment (GFR <60 mL/min/1.73 m²).

Patient with cardiac failure, ischaemic heart disease, cerebrovascular disease, angina pectoris, aortic or mitral valve stenosis, hypertrophic cardiomyopathy with outflow tract obstruction, collagen vascular disease (e.g. SLE), diabetes mellitus, volume depletion, unilateral or bilateral renal artery stenosis; hyperkalaemia or risk factors of hyperkalaemia. Patient undergoing major surgery and desensitisation therapy with hymenoptera venom. Black race. Renal and hepatic impairment. Elderly. Lactation.

Significant: Symptomatic hypotension with or without syncope (particularly after the initial dose), dry and nonproductive cough; hyperkalaemia, renal function deterioration, increased serum creatinine. Rarely, intestinal angioedema, haematologic effects (e.g. neutropenia or agranulocytosis, thrombocytopenia, anaemia), proteinuria; exfoliative dermatitis, Stevens-Johnson syndrome, pemphigoid-like lesion.
Cardiac disorders: Palpitations, chest pain.
Gastrointestinal disorders: Nausea, vomiting, dyspepsia, epigastric pain.
General disorders and administration site conditions: Fatigue, oedema (joint and peripheral).
Infections and infestations: Viral infection.
Investigations: Increased BUN, ALT, AST, gamma-glutamyl transferase.
Musculoskeletal and connective tissue disorders: Pain in limbs.
Nervous system disorders: Dizziness, headache, somnolence, cerebrovascular disorders, paraesthesia.
Respiratory, thoracic and mediastinal disorders: Bronchitis, upper respiratory tract infection, rhinitis.
Skin and subcutaneous tissue disorders: Rash, pruritus.
Potentially Fatal: Angioneurotic oedema associated with laryngeal oedema; anaphylactic/anaphylactoid reactions. Rarely, cholestatic jaundice or hepatitis that may progress to fulminant hepatic necrosis.

This drug may cause dizziness or lightheadedness, if affected, do not drive or operate machinery.

Monitor BUN, serum creatinine, WBC, and serum K levels. Obtain CBC with differential at baseline, every 2 weeks during the 1st 3 months of treatment and periodically thereafter in patients with collagen vascular disease and renal impairment.

Symptoms: Severe hypotension, bradycardia, electrolyte disturbances, stupor, shock and renal failure. Management: If ingestion is recent, perform gastric lavage or administer adsorbents and Na sulfate within 30 minutes following intake. Closely observe the patient, preferably in an intensive care unit. Frequently monitor serum electrolytes and creatinine. In case of hypotension, place the patient in a shock position and immediately give salt and volume supplementation; consider treatment with angiotensin II. Administer atropine for the treatment of bradycardia and extensive vagal reactions; may consider the use of a pacemaker. Haemodialysis may be performed to remove imidapril and imidaprilat from the circulation.

Increased risk of hyperkalaemia with K-sparing diuretics (e.g. spironolactone, triamterene, amiloride), K supplements or K-containing salt substitutes. Increased serum concentration and toxicity of lithium. NSAIDs (e.g. indometacin, aspirin), rifampicin, and sympathomimetics may decrease the antihypertensive effect of imidapril. May increase the risk of leucopenia with allopurinol, procainamide, and immunosuppressants. Enhanced hypotensive effect with other antihypertensive agents, diuretics (e.g. hydrochlorothiazide), nitrates, TCAs, and neuroleptics. May cause nitritoid reactions (e.g. facial flushing, nausea, vomiting, hypotension) with Na aurothiomalate. May enhance the hypoglycaemic effect of antidiabetic agents (e.g. insulin).
Potentially Fatal: Increased risk of hypotension, hyperkalaemia, and reduced renal function (including acute renal failure) with aliskiren. May result in severe anaphylactoid reactions when administered in patients undergoing LDL apheresis with dextran sulfate cellulose adsorption and haemodialysis with high-flux acrylonitrile methallyl sulfonate Na membranes.

High-fat meals significantly decrease imidapril absorption.

May result in false-negative aldosterone/renin ratio (ARR).

Description: Imidapril, a prodrug of imidaprilat, is a competitive ACE inhibitor that prevents the conversion of angiotensin I to angiotensin II, a potent vasoconstrictor responsible for arterial vasoconstriction, increased blood pressure, and stimulation of aldosterone secretion. This action leads to lower angiotensin II levels, thereby increasing plasma renin activity and reducing aldosterone secretion.
Duration: 24 hours.
Pharmacokinetics:
Absorption: Rapidly but incompletely absorbed from the gastrointestinal tract. Reduced absorption with high-fat meals. Bioavailability: Approx 70% (imidapril); approx 42% (imidaprilat). Time to peak plasma concentration: Approx 2 hours (imidapril); 6-8 hours (imidaprilat).
Distribution: Plasma protein binding: 85% (imidapril); 53% (imidaprilat).
Metabolism: Metabolised in the liver via hydrolysis to imidaprilat (active metabolite).
Excretion: Via faeces (approx 50%); urine (approx 40%). Elimination half-life: Imidapril: Approx 2 hours. Imidaprilat: 7-9 hours (initial); >24 hours (terminal).

Source: National Center for Biotechnology Information. PubChem Compound Summary for CID 5464343, Imidapril. https://pubchem.ncbi.nlm.nih.gov/compound/Imidapril. Accessed May 26, 2022.

Store below 30°C.

ACE Inhibitors/Direct Renin Inhibitors

C09AA16 - imidapril ; Belongs to the class of ACE inhibitors. Used in the treatment of cardiovascular disease.

Anon. Imidapril. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 04/05/2022.

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Tanatril 20 mg Tablets (Northumbria Pharma Ltd.). MHRA. https://products.mhra.gov.uk. Accessed 04/05/2022.

Tanatril Tablets 5 mg, 10 mg (Mitsubishi Tanabe Pharma Malaysia Sdn. Bhd.). National Pharmaceutical Regulatory Agency - Ministry of Health Malaysia. https://www.npra.gov.my. Accessed 04/05/2022.