Zestril 20mg is a prescription medication containing lisinopril dihydrate, equivalent to 20 mg of anhydrous lisinopril. It comes in a package of 28 tablets and is manufactured by AstraZeneca. This medication should not be used during pregnancy. This medication contains lisinopril dihydrate equivalent to 20 mg anhydrous lisinopril per tablet. The package contains 28 tablets. Important warning: This medication should not be used during pregnancy. Patients should consult their doctor and refer to the product leaflet for complete information about usage, warnings, and precautions.