There are eight renin angiotensin-converting enzyme inhibitors, mainly including captopril, enalapril, benazepril, lenopril, perindopril, fosinopril, cilazapril, and ramipril. Angiotensin converting enzyme inhibitors are broadly categorized into three generations. The first generation has sulfhydryl as the core group, and the representative drug is captopril; the second generation has carboxyl as the core group, and the representative drugs are enalapril, benazepril, perindopril, etc.; the third generation has phosphonyl as the core group, and the representative drug is fosinopril. Currently, captopril and enalapril are frequently used in clinical practice. Angiotensin-converting enzyme inhibitors are compounds that inhibit the activity of angiotensin-converting enzyme, and their main pharmacological effect is to inhibit the activity of ACE, reduce the production of Ang II, thus blocking the Ang II-mediated vasoconstriction, water-sodium retention, blood pressure elevation and other effects on the renin-angiotensin-aldosterone system. If you are a patient who needs to take angiotensin converting enzyme inhibitors, it is recommended that you take them under the guidance of your doctor’s standardization, and you should not use them on your own.