What is Lisinopril?
Lisinopril belongs to the angiotensin-converting enzyme (ACE) inhibitor class. It relaxes blood vessels to lower blood pressure and improve blood flow to the heart. It is taken orally once a day, with or without food. Common side effects are dizziness, cough, and hypotension.
Generic Name
lisinopril
Brand Names
Prinivil, Zestril, Qbrelis, Acerbon, Carace, Diroton, Lisihexal, Lisinocomp, Lysinoton.
Drug Classification
Therapeutic class: antihypertensives. Pharmacologic class: ACE inhibitors.
Indications and Therapeutic Effects
Hypertension and heart failure are the main indications. Lisinopril also improves survival after an acute myocardial infarction, typically started in patients within the past 24 hours of a heart attack and continued for several weeks. It manages diabetic nephropathy, reducing the risk of kidney failure in patients with diabetes and high blood pressure. It is used off-label for migraine prophylaxis.
Mechanism of Action
Lisinopril blocks ACE, the enzyme that converts angiotensin I into angiotensin II. Angiotensin II is a potent vasoconstrictor that narrows vessels and raises blood pressure. Less angiotensin II means relaxed vessels, lower pressure, and better blood flow to the heart and other organs.
Precautions and Contraindications
Precautions
Hypotension is the early risk, especially in patients who are volume-depleted, have renal impairment, or take other blood-pressure-lowering drugs. Monitor blood pressure regularly. Lisinopril is cleared renally and accumulates in renal impairment, so dosage may need adjustment. It raises potassium, particularly with renal impairment or other potassium-raising drugs, so monitor levels. It can cause angioedema, a life-threatening swelling of the face, lips, tongue, or throat that can happen at any point in therapy; Black patients have a higher reported incidence than non-Black patients (DailyMed Prescribing Information). Lisinopril carries an FDA boxed warning for fetal toxicity: do not use it in pregnancy, and discontinue it as soon as pregnancy is detected, because drugs acting on the renin-angiotensin system in the second and third trimesters can cause fetal renal failure, oligohydramnios, and death (DailyMed Prescribing Information). Discontinue before surgery or anesthesia because of the hypotension risk.
Contraindications
History of angioedema. Hypersensitivity to any ACE inhibitor. Pregnancy. Bilateral renal artery stenosis.
Drug Interactions
Drug-Drug
Diuretics raise the risk of hypotension and hyperkalemia. NSAIDs such as ibuprofen and naproxen blunt the antihypertensive effect and add renal dysfunction risk. Potassium-sparing diuretics and potassium supplements drive hyperkalemia. Lithium levels climb because of decreased renal excretion, risking lithium toxicity. Lisinopril enhances the hypoglycemic effect of insulin and oral hypoglycemics. Gold compounds raise the risk of neutropenia. Other antihypertensives add to the hypotension.
Drug-Natural Products
Potassium supplements, potassium-rich foods like bananas, and potassium-containing salt substitutes all push hyperkalemia. Garlic, ginger, and hawthorn lower blood pressure and add to the hypotension. Grapefruit juice can raise lisinopril levels. St. John's Wort speeds its breakdown in the liver and weakens the effect. Ginseng can raise blood pressure. Coenzyme Q10 (CoQ10) can lower it.
Drug-Food
Grapefruit juice raises drug levels. High-potassium foods such as bananas and leafy greens raise hyperkalemia risk. Alcohol adds to hypotension and should be avoided. Tyramine-rich foods (aged cheeses, cured meats, some fermented foods) can trigger hypertensive crisis. Large amounts of caffeine can raise blood pressure.
Adverse Effects
Hypotension, with dizziness, lightheadedness, and fainting. Hyperkalemia, which can cause weakness, fatigue, and arrhythmias. Angioedema, rare but potentially fatal, needing emergency care. Persistent dry cough that may force discontinuation. Rash or itching. Renal impairment, especially with preexisting kidney disease. Neutropenia, rare, raising infection risk. Hepatotoxicity, rare, especially with preexisting liver disease. Sexual dysfunction, including erectile dysfunction and decreased libido.
Administration Considerations
Available Forms
- Oral solution: 1 mg/mL.
- Tablets: 2.5 mg, 5 mg, 10 mg, 20 mg, 30 mg, 40 mg.
- In combination with: hydrochlorothiazide (Prinzide, Zestoretic).
Dosage for Children
- PO (Children ≥6 yr)
- Hypertension. 0.07 mg/kg once daily (up to 5 mg/day), may be titrated every 1-2 wk up to 0.6 mg/kg/day (or 40 mg/day).
- Renal Impairment. CCr <30 mL/min, contraindicated.
Dosage for Adults
- PO (Adults)
- Hypertension. 10 mg once daily, can be increased up to 20-40 mg/day (initiate therapy at 5 mg/day in patients receiving diuretics).
- HF. 5 mg once daily; may be titrated every 2 wk up to 40 mg/day; begin with 2.5 mg once daily in patients with hyponatremia (serum sodium <130 mEq/L).
- Post-MI. 5 mg once daily for 2 days, then 10 mg daily.
- Renal Impairment. CCr 10-30 mL/min, begin with 5 mg once daily; may be slowly titrated up to 40 mg/day; CCr <10 mL/min, begin with 2.5 mg once daily; may be slowly titrated up to 40 mg/day.
Pharmacokinetics
Lisinopril is well absorbed orally, with a bioavailability of approximately 25%, reaching peak plasma concentrations within 7 hours. It distributes widely (heart, kidneys, liver, lungs) and is minimally protein-bound at about 10%. It is not extensively metabolized and is eliminated unchanged in the urine. Elimination half-life is approximately 12 hours.
Nursing Considerations for Lisinopril
Nursing Assessment
Check blood pressure, heart rate, and respiratory rate before and after dosing to confirm pressure is controlled and to catch adverse reactions. Assess renal function before starting and monitor serum creatinine and BUN, since lisinopril can worsen renal function in patients with kidney disease. Take a full medical history, including allergies and prior drug reactions, because conditions like a history of angioedema or renal disease change whether this drug is safe. Take a medication history, including OTC drugs, supplements, and herbals, to catch interactions with diuretics or potassium supplements. Watch for symptoms of hypertension or heart failure such as shortness of breath, chest pain, and fatigue. Monitor electrolytes, especially potassium, because hyperkalemia can cause serious cardiac complications. Watch for angioedema (swelling of the face, lips, tongue, or throat), which is life-threatening and needs early recognition. Check adherence, including the dosing schedule and missed doses, since noncompliance means poor pressure control. Assess for side effects such as dizziness, dry cough, and headache. Assess lifestyle factors (smoking, diet, exercise) that affect pressure control.
Nursing Diagnosis
Decreased cardiac output from the heart's inability to pump blood effectively. Ineffective therapeutic regimen management related to poor adherence. Risk for injury related to drug-induced hypotension. Risk for ineffective renal function related to therapy. Anxiety related to potential adverse effects such as angioedema or hyperkalemia. Noncompliance related to cost or lack of understanding of therapy.
Nursing Interventions
Give lisinopril as prescribed. Correct volume depletion before starting therapy when possible, because lisinopril can deepen the depletion and trigger hypotension and renal impairment. Collaborate with the healthcare team on medication adjustments and referrals.
Patient Education and Teaching
Take the medication at the same time each day, even when feeling well. Take a missed dose as soon as possible, but skip it if it is almost time for the next dose, and never double up. Do not stop an ACE inhibitor without a provider's direction, because abrupt withdrawal can spike blood pressure and trigger a heart attack or stroke. Avoid salt substitutes and high-potassium or high-sodium foods unless a provider directs otherwise, since they drive hyperkalemia or counteract the drug. Change positions slowly to limit orthostatic hypotension; alcohol, prolonged standing, exercise, and hot weather make it worse. Report all medications, vitamins, and herbal products. Avoid driving and other activities needing alertness until the drug's effect is known, since it causes dizziness and fatigue. Report side effects such as dizziness, dry cough, or headache promptly. Share past and present medical conditions, since kidney disease or diabetes may change dosing. Taste impairment generally resolves within 8-12 weeks even with continued therapy. Diabetic patients should monitor blood glucose closely, especially in the first month, since lisinopril may cause hypoglycemia. Women of childbearing age should use contraception and notify the provider if pregnancy is planned or suspected; lisinopril is teratogenic, so discontinue it as soon as pregnancy is detected. Keep a healthy lifestyle: regular exercise, healthy diet, no smoking, limited alcohol. Keep followup appointments for monitoring and dose adjustment. Reinforce nondrug measures for hypertension (weight reduction, low-sodium diet, smoking cessation, alcohol moderation, exercise, stress management); the drug controls but does not cure hypertension. Teach the patient and family correct blood-pressure technique, check it at least weekly, and report significant changes, since poor technique gives false readings and leads to wrong dosing decisions.
Evaluation and Desired Outcomes
Blood pressure within normal range, lowering stroke, heart attack, and kidney disease risk. Improved heart failure symptoms (less dyspnea, fatigue, and swelling). Minimal, well-tolerated side effects. Stable or improving renal function. Adherence to the prescribed regimen.
Frequently Asked Questions
What is the most dangerous side effect of lisinopril? Angioedema, a rapid swelling of the face, lips, tongue, or throat that can obstruct the airway. It can occur at any point in therapy, is reported more often in Black patients, and requires stopping the drug and seeking emergency care (DailyMed Prescribing Information).
Can lisinopril be taken during pregnancy? No. It carries an FDA boxed warning for fetal toxicity and should be stopped as soon as pregnancy is detected. ACE inhibitors used in the second and third trimesters can cause fetal kidney failure, low amniotic fluid, and death, so women of childbearing age should use reliable contraception.
Why does lisinopril cause a dry cough? ACE inhibitors raise levels of bradykinin and substance P in the airway, which triggers a persistent dry, hacking cough in some patients. The cough is harmless but bothersome and is a common reason the drug is switched, often to an ARB.
What labs are monitored on lisinopril? Serum potassium and renal function (creatinine and BUN). Lisinopril raises potassium and can worsen kidney function, especially in renal impairment, with diuretics, or with potassium supplements or salt substitutes.
Why is the first dose risky in someone on a diuretic? Patients who are volume-depleted or already taking a diuretic can have a steep drop in blood pressure with the first dose. Correct volume depletion when possible and start at a lower dose in these patients.
Can lisinopril be stopped abruptly? It should not be stopped without provider direction. Abrupt withdrawal can cause blood pressure to rebound and raise the risk of a cardiac event, so any change should be made under medical guidance.