Enalapril

Pronunciation

Enalapril 10mg

Enalapril 5mg

Generic Name:	Enalapril
Class:	Cardiovascular Drug
Subclass:	ACE inhibitors
Legal Classification:	P1S1S3

Drug Names

Generic Name 藥物化學名稱	HA Code 藥物代碼	Legal Classification法律藥物分類
Enalapril Maleate Tablet 2.5mg		P1S1S3
Enalapril Maleate Tablet 5mg	ENAL02	P1S1S3
Enalapril Maleate Tablet 10mg	ENAL03	P1S1S3
Enalapril Maleate Tablet 20mg	ENAL01	P1S1S3

Mechanism of Action

Enalapril is an inhibitor of angiotensin-I converting enzyme (ACE inhibitor). The beneficial effects of ACE inhibitors appear to result primarily from the suppression of the plasma renin-angiotensin-aldosterone system. Renin is synthesized by the kidneys and released into the circulation where it converts angiotensinogen to angiotensin-I. Angiotensin-I is then converted by angiotensin converting enzyme to angiotensin-II. Angiotensin-II is a potent vasoconstrictor responsible for arterial vasoconstriction and increased blood pressure, as well as for stimulation of the adrenal gland to secrete aldosterone. Inhibition of ACE results in decreased plasma angiotensin-II, which leads to decreased vasopressor activity and to reduced aldosterone secretion. Enalapril is used in the treatment of hypertension and heart failure. It may also be given prophylactically to patients with asymptomatic left ventricular dysfunction to delay the onset of symptomatic heart failure, and has been used in patients with left ventricular dysfunction to reduce the incidence of coronary ischaemic events, including myocardial infarction.

Route of Administration

Enalapril is administered orally as enalapril maleate.

Dosage

Hypertension

• Adult: initially 5 mg once daily, lower initial doses may be required when used in addition to diuretic or in renal impairment; maintenance 20 mg once daily; maximum 40 mg/day.

Heart failure

• Adult: initially 2.5 mg once daily, increased if tolerated to 10-20 mg twice daily, doses to be increased gradually over 2-4 weeks

Onset of antihypertensive activity was usually seen at 1 hour, with peak reduction of blood pressure achieved by 4 to 6 hours after administration.

The duration of effect is dose related. However, at recommended doses, antihypertensive and haemodynamic effects have been shown to be maintained for at least 24 hours.

Side Effects

System Organ Class	Frequency	Adverse reactions
Nervous system disorders	Common	Dizziness, headache, taste alteration
Psychiatric disorders	Common	depression
Uncommon	Confusion, insomnia
Respiratory disorders	Common	Dry, irritating (non-productive) cough and dyspnoea
Eye disorders	Common	Blurred vision
Skin disorders	Common	Rash Oedema of the face, extremeties, lips, tongue, glottis and/or larynx
Gastro-intestinal disorders	Common	Abdominal pain, nausea, , diarrhoea
Uncommon	Constipation, anorexia, peptic ulcer
Rare	Stomatitis, small bowel angioedema
Very rare	Glossitis, pancreatitis
Cardiac disorders	common	Chest pain, arrhythmia, tachycardia
Vascular disorder	common	Hypotension
Uncommon	flushing
Rare	Raynaud’s syndrome