Lisinopril

Drug Information: Lisinopril

Lisinopril is an angiotensin-converting enzyme (ACE) inhibitor used primarily in the treatment of hypertension, heart failure, and to improve survival after a heart attack. By inhibiting ACE, lisinopril reduces the production of angiotensin II, a potent vasoconstrictor, leading to vasodilation and decreased blood pressure. It also reduces aldosterone secretion, promoting sodium excretion and further reducing blood volume and blood pressure. Lisinopril is a long-acting ACE inhibitor, typically administered once daily, making it a convenient option for many patients. It’s available in various strengths and is often used as a first-line treatment for hypertension, either alone or in combination with other antihypertensive medications.

Category

Antihypertensive

Mechanism of Action

Lisinopril’s mechanism of action revolves around its role as an ACE inhibitor. Angiotensin-converting enzyme (ACE) is a crucial enzyme in the renin-angiotensin-aldosterone system (RAAS). This system plays a central role in regulating blood pressure and fluid balance. ACE converts angiotensin I to angiotensin II. Angiotensin II is a potent vasoconstrictor, causing blood vessels to narrow, which increases blood pressure. It also stimulates the release of aldosterone from the adrenal glands. Aldosterone promotes sodium and water retention by the kidneys, further increasing blood volume and blood pressure.

Lisinopril binds to ACE, inhibiting its activity. This inhibition reduces the production of angiotensin II. As a result, blood vessels dilate, leading to a decrease in blood pressure. The reduced angiotensin II also lowers aldosterone levels, promoting the excretion of sodium and water, which further lowers blood volume and blood pressure.

Furthermore, ACE is also responsible for the breakdown of bradykinin, a vasodilator. By inhibiting ACE, lisinopril leads to increased levels of bradykinin. This contributes to the vasodilation effect, further lowering blood pressure. The reduction in angiotensin II also has beneficial effects on the heart by reducing cardiac remodeling and improving cardiac function, particularly in patients with heart failure or after a myocardial infarction. Lisinopril does not require metabolic activation, unlike some other ACE inhibitors, making its onset of action more predictable.

Clinical Uses

Lisinopril is primarily used for the management of hypertension (high blood pressure). It effectively lowers blood pressure, reducing the risk of cardiovascular events such as stroke, heart attack, and kidney damage. It is often used as a first-line treatment for hypertension, either alone or in combination with other antihypertensive medications.

In patients with heart failure, lisinopril helps to improve heart function, reduce symptoms such as shortness of breath and edema, and increase survival. It achieves this by reducing afterload (the resistance the heart pumps against) and preload (the volume of blood returning to the heart), thus decreasing the workload on the heart.

Following a myocardial infarction (heart attack), lisinopril is used to improve survival and reduce the risk of subsequent cardiac events. It helps to prevent remodeling of the heart and improve left ventricular function.

Lisinopril is also used in the treatment of diabetic nephropathy (kidney disease caused by diabetes). By reducing blood pressure and protecting the kidneys, lisinopril helps to slow the progression of kidney disease in patients with diabetes. Due to its ability to protect the kidneys, it may also be used in other forms of chronic kidney disease. Off-label uses may include the prevention of migraines.

Dosage

Adults:

• Hypertension: The usual starting dose is 10 mg once daily. The dosage may be adjusted as needed, with a typical maintenance dose of 20-40 mg once daily. The maximum dose is generally 80 mg per day.
• Heart Failure: The initial dose is usually 2.5-5 mg once daily, gradually increased as tolerated to a target dose of 20-40 mg once daily.
• Post-Myocardial Infarction: Initially 5 mg within 24 hours of the heart attack, followed by 5 mg after 24 hours, 10 mg after 48 hours, and then 10 mg once daily.

Pediatrics (6 years and older):

• Hypertension: The starting dose is typically 0.07 mg/kg once daily (up to 5 mg). The dosage is adjusted based on blood pressure response, with a maximum dose of 0.61 mg/kg (up to 40 mg) once daily.

Route of Administration: Oral. Lisinopril is typically taken once daily, with or without food.

Indications

Common indications for Lisinopril include:

• Hypertension (high blood pressure)
• Heart Failure
• Post-Myocardial Infarction (heart attack)
• Diabetic Nephropathy (kidney disease due to diabetes)

Contraindications

Lisinopril is contraindicated in the following situations:

• History of angioedema (swelling of the face, lips, tongue, or throat) related to previous ACE inhibitor therapy.
• Hereditary or idiopathic angioedema.
• Pregnancy (especially during the second and third trimesters).
• Concomitant use with aliskiren in patients with diabetes.
• Hypersensitivity to Lisinopril or other ACE inhibitors.

FAQ

1. What is Lisinopril used for?

   Lisinopril is used to treat high blood pressure (hypertension), heart failure, and to improve survival after a heart attack. It can also be used to treat kidney problems caused by diabetes.

2. How does Lisinopril work?

   Lisinopril works by blocking the production of a substance called angiotensin II, which narrows blood vessels. By blocking angiotensin II, Lisinopril helps to relax and widen blood vessels, lowering blood pressure.

3. What are the common side effects of Lisinopril?

   Common side effects include dizziness, cough, fatigue, headache, and low blood pressure. Some people may experience kidney problems or high potassium levels in the blood.

4. Can I drink alcohol while taking Lisinopril?

   Drinking alcohol while taking Lisinopril can lower your blood pressure too much, causing dizziness or fainting. It’s best to limit or avoid alcohol while taking this medication.

5. What should I do if I miss a dose of Lisinopril?

   If you miss a dose, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not double your dose to make up for the missed one.

6. Can Lisinopril be taken during pregnancy?

   No, Lisinopril should not be taken during pregnancy, especially during the second and third trimesters. It can cause serious harm to the unborn baby.

7. How long does it take for Lisinopril to start working?

   Lisinopril starts working within a few hours to lower blood pressure, but it may take several weeks to see the full effects of the medication.

8. Can Lisinopril cause a cough?

   Yes, a dry, persistent cough is a common side effect of Lisinopril and other ACE inhibitors. If the cough becomes bothersome, contact your doctor. They may switch you to a different type of medication.