The reference site for Lisinopril. Lisinopril is a drug of the angiotensin-converting enzyme (ACE) inhibitor class used primarily in treatment of high blood pressure, heart failure, and after heart attacks. It is also used for preventing kidney and eye complications in people with diabetes. Its indications, contraindications, and side effects. Product Code 50090-3765. Lisinopril by A-s Medication Solutions is a yellow capsule tablet about 8 mm in size, imprinted with h;145. The product is a human prescription drug with active ingredient (s) lisinopril. Lisinopril is in a class of medications called angiotensin-converting enzyme (ACE) inhibitors. It works by decreasing certain chemicals that tighten the blood vessels, so blood flows more smoothly and the heart can pump blood more efficiently. High blood pressure is a common condition and when not treated, can cause damage to the brain, heart.