Usage
Lisinopril is primarily prescribed for:
- Hypertension (High Blood Pressure): It’s a first-line treatment option, effectively lowering blood pressure.
- Heart Failure: Improves symptoms and reduces mortality risk in patients with heart failure.
- Acute Myocardial Infarction (Heart Attack): Reduces mortality and the risk of subsequent heart failure after a heart attack.
- Diabetic Nephropathy (Kidney Damage from Diabetes): (Off-label) Slows the progression of kidney damage in patients with diabetes.
Pharmacological Classification: Angiotensin-Converting Enzyme (ACE) inhibitor.
Mechanism of Action: Lisinopril inhibits the angiotensin-converting enzyme, preventing the conversion of angiotensin I to angiotensin II. This reduces vasoconstriction, aldosterone secretion, and sodium reabsorption, ultimately lowering blood pressure and reducing strain on the heart.
Alternate Names
No commonly used alternate generic names.
Brand Names: Zestril, Prinivil, Qbrelis.
How It Works
Pharmacodynamics: Lisinopril’s primary effect is vasodilation (widening of blood vessels), reducing peripheral vascular resistance and lowering blood pressure. It also reduces sodium and water retention by inhibiting aldosterone secretion.
Pharmacokinetics:
- Absorption: Orally administered lisinopril is incompletely absorbed (about 25%), and food doesn’t significantly affect its absorption.
- Metabolism: Lisinopril isn’t metabolized in the liver and remains unchanged in the body.
- Elimination: Primarily excreted unchanged through the kidneys.
Mode of Action: Lisinopril competitively binds to and inhibits ACE, preventing the formation of angiotensin II. This reduces angiotensin II’s vasoconstricting effects and diminishes aldosterone secretion. Reduced aldosterone leads to decreased sodium and water retention, further contributing to blood pressure reduction.
Receptor Binding/Enzyme Inhibition: Inhibits ACE.
Elimination Pathways: Renal excretion (unchanged).
Dosage
Standard Dosage
Adults:
- Hypertension: Initial dose is typically 10 mg once daily, titrated up to 20-40 mg daily as needed. Maximum dose: 80 mg/day, though benefits beyond 40 mg are unclear.
- Heart Failure: Initial dose is 2.5-5 mg once daily, titrated up to a maximum of 40 mg daily as tolerated.
- Post-Myocardial Infarction: Initial dose 5 mg within 24 hours, followed by 5 mg after 24 hours, 10 mg after 48 hours, and then 10 mg once daily for at least 6 weeks.
- Diabetic Nephropathy: Initial dose is usually 10 mg, titrated up to a maximum of 40 mg daily.
Children (6 years and older):
- Hypertension: Initial dose 0.07 mg/kg (up to 5 mg) once daily, titrated up to a maximum of 0.61 mg/kg (up to 40 mg) daily.
- Use in children younger than 6 years is not recommended.
Special Cases:
- Elderly Patients: Start with a lower dose (e.g., 2.5-5 mg) and titrate cautiously.
- Patients with Renal Impairment: Reduced doses are necessary, based on creatinine clearance.
- Patients with Hepatic Dysfunction: No dosage adjustment is typically needed.
- Patients with Comorbid Conditions (e.g., Diabetes, Cardiovascular Disease): Close monitoring is necessary. Consider lower initial doses and cautious titration.
Clinical Use Cases
Lisinopril’s dosage in clinical settings like intubation, surgical procedures, mechanical ventilation, ICU use, and emergency situations needs to be determined on a case-by-case basis, considering the patient’s specific condition and hemodynamic stability. For example, a lower starting dose may be necessary in cases of hypotension or renal impairment.
Dosage Adjustments
Dose adjustments are necessary for patients with renal impairment, based on creatinine clearance. Lower starting doses and cautious titration are recommended in elderly patients and those with comorbid conditions.
Side Effects
Common Side Effects:
- Cough (dry, persistent)
- Dizziness, lightheadedness (especially upon standing)
- Headache
- Nausea, diarrhea
- Fatigue
- Hypotension
Rare but Serious Side Effects:
- Angioedema (swelling of face, lips, tongue, throat, or extremities)
- Hyperkalemia (high potassium levels)
- Renal impairment
- Neutropenia, agranulocytosis (low white blood cell count)
- Hepatic dysfunction
- Syncope (fainting)
Long-Term Effects:
Chronic kidney disease might occur with long-term use, especially in patients with pre-existing renal impairment.
Adverse Drug Reactions (ADR):
Angioedema, acute renal failure, and severe hypotension are ADRs requiring immediate medical intervention.
Contraindications
- History of angioedema related to ACE inhibitor use.
- Hereditary or idiopathic angioedema.
- Concomitant use of aliskiren in patients with diabetes.
- Concomitant use or use within 36 hours of a neprilysin inhibitor (e.g., sacubitril/valsartan).
- Pregnancy (second and third trimesters).
- Hypersensitivity to lisinopril.
Drug Interactions
- Diuretics: Increased risk of hypotension.
- Potassium-sparing diuretics (e.g., spironolactone): Increased risk of hyperkalemia.
- NSAIDs: Reduced antihypertensive effect and increased risk of renal impairment.
- Lithium: Increased lithium levels.
- Aliskiren (in patients with diabetes): Increased risk of side effects.
- Neprilysin inhibitors (e.g., sacubitril/valsartan): Increased risk of angioedema.
- mTOR inhibitors: Increased risk of angioedema
Pregnancy and Breastfeeding
- Pregnancy Safety Category: D (second and third trimesters); C (first trimester).
- Fetal Risks: ACE inhibitors can cause fetal kidney damage, growth restriction, and even fetal death, especially in the second and third trimesters.
- Breastfeeding: Limited data is available; not recommended, especially for preterm infants or newborns. Alternatives like enalapril or captopril, which have more established safety profiles, are preferred.
Drug Profile Summary
- Mechanism of Action: ACE inhibitor, reduces angiotensin II and aldosterone.
- Side Effects: Cough, dizziness, headache, hypotension, angioedema, hyperkalemia.
- Contraindications: Angioedema history, concomitant aliskiren/neprilysin inhibitor use, pregnancy (2nd/3rd trimesters).
- Drug Interactions: Diuretics, NSAIDs, lithium, aliskiren, neprilysin inhibitors.
- Pregnancy & Breastfeeding: Contraindicated in 2nd/3rd trimesters of pregnancy; use with caution during breastfeeding.
- Dosage: Hypertension: 10-40 mg daily; Heart Failure: 2.5-40 mg daily; Post-MI: Initially 5 mg, then 10 mg daily.
- Monitoring Parameters: Blood pressure, renal function (serum creatinine, potassium), signs of angioedema.
Popular Combinations
Lisinopril is often combined with hydrochlorothiazide (a diuretic) for synergistic blood pressure lowering effects.
Precautions
- General Precautions: Monitor renal function, potassium levels, and blood pressure.
- Specific Populations: Avoid in pregnancy (2nd/3rd trimesters), use with caution in breastfeeding. Start with lower doses in elderly and patients with renal impairment.
- Lifestyle Considerations: Excessive alcohol intake may worsen hypotension.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Lisinopril?
A: The dosage varies based on the condition: Hypertension (10-40 mg daily), Heart Failure (2.5-40 mg daily), Post-MI (initially 5 mg, then 10 mg daily). Pediatric and renal impairment doses require adjustments.
Q2: What are the most common side effects?
A: Cough, dizziness, headache, and fatigue.
Q3: Can Lisinopril be used during pregnancy?
A: Contraindicated during the second and third trimesters due to the risk of fetal harm.
Q4: What are the serious side effects to watch for?
A: Angioedema, hyperkalemia, and acute renal failure.
Q5: What medications interact with Lisinopril?
A: Diuretics, NSAIDs, lithium, aliskiren, and neprilysin inhibitors.
Q6: How does Lisinopril work to lower blood pressure?
A: It inhibits ACE, reducing angiotensin II formation and thus vasodilation and lowering blood pressure.
Q7: Can I take Lisinopril with other blood pressure medications?
A: It can be combined with other antihypertensives, but careful monitoring is crucial, especially with diuretics.
Q8: What should I do if I miss a dose of Lisinopril?
A: Take the missed dose as soon as you remember, unless it is almost time for the next dose. Do not double the dose.
A: Seek immediate medical attention if you experience symptoms of angioedema (facial swelling, difficulty breathing), signs of hyperkalemia (muscle weakness, irregular heartbeat), or severe hypotension (dizziness, fainting).
As of February 16, 2025, this information is current, but medical knowledge is constantly evolving. Always consult up-to-date resources and guidelines for the most recent recommendations.
