Last reviewed 2026-04-20 · How we verify

Zestril (lisinopril)

Inhibits angiotensin-converting enzyme (ACE), preventing conversion of angiotensin I to angiotensin II, lowering blood pressure and reducing cardiac workload.

Lisinopril (Zestril/Prinivil) is the most prescribed ACE inhibitor in the US, approved in 1987. Unique among ACE inhibitors as it requires no hepatic activation. Available generically worldwide.

At a glance

Mechanism of action

Lisinopril is a lysine analog of enalaprilat and the third ACE inhibitor approved in the US. Unlike most ACE inhibitors, it is not a prodrug and does not require hepatic activation, making it suitable for patients with liver disease. It is the most prescribed ACE inhibitor in the United States, with proven benefits in heart failure, post-MI, and diabetic nephropathy.

Approved indications

• Chronic heart failure
• Hypertensive disorder
• Myocardial infarction
• Superficial Ocular Infection

Boxed warnings

• WARNING: FETAL TOXICITY When pregnancy is detected, discontinue lisinopril and hydrochlorothiazide tablets as soon as possible. Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus. See Warnings, Fetal Toxicity .

Common side effects

• Hypotension
• Headache
• Dizziness
• Cough
• Chest pain
• Hyperkalemia
• Blood urea nitrogen increase
• Serum creatinine increase

Serious adverse events

• Renal dysfunction
• Pancreatitis
• Stevens-Johnson syndrome
• Toxic epidermal necrolysis
• Bone marrow depression
• Hemolytic anemia
• Leukopenia/neutropenia
• Thrombocytopenia
• Vasculitis
• Myocardial infarction

Key clinical trials

• Safety and Pharmacokinetics of Lisinopril in Pediatric Kidney Transplant Recipients (Phase 1)
• Is There an Adverse Drug Reaction Between Renin-Angiotensin System Blockade and Inhaled Anesthetics? - A Pilot Study. Optional Deoxyribo-Nucleic Acid Donation for the Study of Hypertension. (Phase 4)
• PITT0908: Clinical Trial of Coenzyme Q10 and Lisinopril in Muscular Dystrophies (Phase 2)
• PESCA - A Randomised Controlled Trial of a Cardiovascular Polypill Treatment Strategy Compared With Usual Care on Carotid Intima-media Thickness in Individuals at High Risk of Cardiovascular Disease (Phase 3)
• NCT00000542 (Phase 3)
• Novel Therapies for Resistant Focal Segmental Glomerulosclerosis (Phase 2)
• A Randomized, Balanced, Open Label, Two Treatment, Two Period, Two Sequence, Single Dose, Crossover, Bioequivalence Study of Lisinopril Tablets 40 mg With Zestril® (Lisinopril) 40 mg Tablets in Normal (Phase 1)
• Prognostic Value of the Circadian Pattern of Ambulatory Blood Pressure for Multiple Risk Assessment (Phase 4)

Patents

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Zestril CI brief — competitive landscape report
• Zestril updates RSS · CI watch RSS
• Generic (originally Merck/AstraZeneca) portfolio CI