VIACE

Indications

• Hypertension
• Congestive heart failure
• Left ventricular dysfunction following myocardial infarction

Dosage

Children: For children aged 1 month to 16 years, the usual starting dose is 0.08 mg/kg once daily, adjusted according to blood pressure response, with a maximum dose of 0.5 mg/kg per day.

Adults: The usual initial dose is 5 mg once daily, which may be increased according to response, with a maximum dose of 40 mg per day.

Mechanism of action

Enalapril exerts its pharmacological effects through the inhibition of angiotensin-converting enzyme (ACE). By blocking ACE, enalapril decreases the conversion of angiotensin I to angiotensin II. This leads to vasodilation, decreased secretion of aldosterone, and reduced reabsorption of sodium and water, ultimately resulting in lower blood pressure and reduced cardiac output.

Pharmacodynamics

The pharmacodynamic effects of enalapril include a reduction in blood pressure, decreased systemic vascular resistance, and a decrease in preload and afterload on the heart. Enalapril's effects can lead to improved exercise tolerance and quality of life in patients with heart failure. Additionally, renal blood flow may be preserved, which is beneficial in patients with certain types of kidney disease.

Pharmacokinetics

Enalapril is well absorbed after oral administration, with peak plasma concentrations occurring approximately one hour after dosing. It undergoes extensive first-pass metabolism, converting to its active metabolite, enalaprilat. The elimination half-life of enalaprilat is approximately 11 hours, and it is primarily excreted by the kidneys. Dosing adjustments may be necessary in patients with renal impairment.

Contra-indications

• History of angioedema associated with previous ACE inhibitor treatment
• Severe renal impairment
• Pregnancy
• Hypersensitivity to enalapril or any component of the formulation

Adverse effects

• Cough
• Hypotension
• Hyperkalemia
• Renal impairment
• Angioedema
• Rash
• Dizziness

Interactions

• Potassium-sparing diuretics may increase the risk of hyperkalemia
• NSAIDs may reduce the antihypertensive effect of enalapril
• Diuretics may enhance the hypotensive effect of enalapril
• Lithium levels may be increased by enalapril

Precautions

• Monitor renal function during treatment, especially in patients with renal impairment
• Use with caution in patients with a history of heart failure
• Consider monitoring potassium levels in patients at risk of hyperkalemia
• Avoid abrupt withdrawal in patients with heart failure

Pregnancy

Enalapril is contraindicated in pregnancy due to the risk of fetal harm.

Breast-feeding

Caution is advised when administering enalapril to breastfeeding mothers as it may pass into breast milk.

Storage

Store in a cool, dry place, protected from light. Keep out of reach of children.

Formulations

• Tablets
• Oral solution