Zestril (lisinopril) is an angiotensin-converting enzyme (ACE) inhibitor prescribed for the management of hypertension, heart failure, and post-myocardial infarction care. It functions by inhibiting the conversion of angiotensin I to angiotensin II, a potent vasoconstrictor, thereby promoting vasodilation and reducing the heart’s workload. This mechanism not only effectively lowers blood pressure but also offers protective benefits for the kidneys in diabetic patients. As a cornerstone in cardiovascular pharmacotherapy, Zestril is recognized for its efficacy, established safety profile, and role in improving long-term patient outcomes.

Features

• Active ingredient: Lisinopril
• Drug class: Angiotensin-converting enzyme (ACE) inhibitor
• Available in tablet formulations: 2.5 mg, 5 mg, 10 mg, 20 mg, 30 mg, 40 mg
• Administration: Oral, once-daily dosing
• Onset of action: Within 1 hour; peak antihypertensive effects at 6 hours
• Duration of action: 24 hours
• Bioavailability: Approximately 25%, not significantly affected by food
• Metabolism: Minimally metabolized; excreted unchanged in urine
• Prescription-only medication

Benefits

• Effectively reduces systolic and diastolic blood pressure, lowering the risk of stroke, heart attack, and kidney damage.
• Improves survival rates and reduces symptoms in patients with congestive heart failure by decreasing cardiac afterload and preload.
• Provides renal protective effects in diabetic patients by reducing proteinuria and slowing the progression of diabetic nephropathy.
• Enhances clinical outcomes following acute myocardial infarction by stabilizing hemodynamics and preventing ventricular remodeling.
• Offers convenient once-daily dosing, promoting adherence and consistent therapeutic coverage.
• Demonstrates a well-established long-term safety and efficacy profile supported by extensive clinical research.

Common use

Zestril is primarily indicated for the treatment of hypertension, either as monotherapy or in combination with other antihypertensive agents. It is also used in the management of heart failure to improve survival and reduce hospitalization when added to standard therapy. Additionally, it is administered within 24 hours of acute myocardial infarction in hemodynamically stable patients to improve survival. Another key application is in diabetic nephropathy, where it is employed to reduce the rate of progression of renal disease in patients with type 2 diabetes and hypertension.

Dosage and direction

The dosage of Zestril must be individualized based on the patient’s clinical condition, renal function, and blood pressure response.

• Hypertension: Initial dose is 10 mg once daily in patients not on diuretics. Maintenance dose ranges from 20 mg to 40 mg administered once a day. Dosage may be adjusted at intervals of at least 2 weeks.
• Heart Failure: Starting dose is 2.5 mg to 5 mg once daily, under close medical supervision. Target maintenance dose is 20 mg to 40 mg daily, given as a single dose.
• Acute Myocardial Infarction: Initiate with 5 mg orally within 24 hours of onset of symptoms, followed by 5 mg after 24 hours, 10 mg after 48 hours, and then 10 mg once daily for 6 weeks.
• Renal Impairment: Dosage adjustment is necessary based on creatinine clearance. For patients with CrCl <30 mL/min or on dialysis, initial dose should be reduced to 2.5 mg daily.

Tablets should be swallowed whole with a glass of water, with or without food. Regular monitoring of blood pressure and renal function is recommended during therapy.

Precautions

• Monitor blood pressure and renal function periodically, especially after initiation or dose adjustment.
• Assess serum potassium levels regularly due to risk of hyperkalemia, particularly in patients with renal impairment, diabetes, or those using potassium-sparing diuretics.
• Use with caution in patients with collagen vascular disease or on immunosuppressant therapy due to increased risk of neutropenia/agranulocytosis.
• Observe for signs of angioedema; discontinue immediately if facial, lip, tongue, glottis, or laryngeal swelling occurs.
• May cause symptomatic hypotension; volume-depleted patients should be corrected prior to initiation.
• Not recommended during pregnancy due to potential fetal harm; should be discontinued as soon as pregnancy is detected.

Contraindications

• History of angioedema related to previous ACE inhibitor therapy.
• Hypersensitivity to lisinopril or any other ACE inhibitor.
• Concomitant use with aliskiren in patients with diabetes.
• Patients with hereditary or idiopathic angioedema.
• Second and third trimester of pregnancy.

Possible side effect

Common side effects may include:

• Dizziness
• Headache
• Persistent dry cough
• Fatigue
• Nausea

Less frequent but serious adverse reactions:

• Angioedema
• Hypotension
• Hyperkalemia
• Renal impairment
• Neutropenia/agranulocytosis
• Hepatic failure (rare)
• Pancreatitis (rare)

Drug interaction

• Diuretics: Potentiate hypotensive effect; monitor for excessive blood pressure drop.
• Potassium-sparing diuretics/potassium supplements: Increased risk of hyperkalemia.
• Lithium: Increased lithium concentrations and toxicity.
• NSAIDs: May reduce antihypertensive effect and increase risk of renal impairment.
• Aliskiren: Contraindicated in diabetic patients due to increased risk of renal impairment, hyperkalemia, and hypotension.
• Gold injections: Nitritoid reactions have been reported with sodium aurothiomalate.
• Oral hypoglycemics/insulin: Enhanced hypoglycemic effect possible.

Missed dose

If a dose is missed, it should be taken as soon as remembered on the same day. If it is near the time for the next dose, skip the missed dose and resume the regular dosing schedule. Do not double the dose to make up for a missed one.

Overdose

Symptoms of overdose may include severe hypotension, bradycardia, circulatory shock, hyperkalemia, renal failure, and electrolyte imbalances. Management involves supportive measures including volume expansion with normal saline to treat hypotension. Lisinopril is dialyzable, and hemodialysis may be considered in cases of significant overdose. Close monitoring of vital signs and electrolyte balance is essential.

Storage

Store at controlled room temperature (20°C to 25°C or 68°F to 77°F), with excursions permitted between 15°C to 30°C (59°F to 86°F). Keep in the original container, tightly closed, and protect from moisture and light. Keep out of reach of children and pets. Do not use after the expiration date printed on the packaging.

Disclaimer

This information is for educational purposes only and does not constitute medical advice. Zestril is a prescription medication and should only be used under the supervision of a qualified healthcare professional. Dosage and treatment decisions must be made by a physician based on individual patient assessment. Always consult with your healthcare provider for diagnosis and treatment recommendations tailored to your specific medical condition.

Reviews

Clinical studies and patient reports consistently demonstrate Zestril’s effectiveness in blood pressure control and cardiovascular risk reduction. Many patients experience significant improvement in hypertension management with once-daily convenience. The dry cough associated with ACE inhibitors is a noted side effect in some individuals, occasionally necessitating alternative therapy. Overall, Zestril remains a widely trusted and frequently prescribed agent in cardiovascular medicine, with long-term data supporting its role in improving patient outcomes across multiple indications.