Perindopril and Benadryl are angiotensin-converting enzyme inhibitors, and there is no clear distinction between good and bad, however, perindopril can be chosen for the treatment of essential hypertension, while Benadryl can be chosen for the treatment of people with congestive heart failure who do not respond well to digitalis or diuretics. Perindopril is an angiotensin-converting enzyme inhibitor, which can inhibit the secretion of aldosterone and reduce the resistance of peripheral arteries. It is mainly used in the treatment of essential hypertension and congestive heart failure. Perindopril can cause headache, fatigue, dizziness and other adverse reactions. People who are allergic to the components of the drug, angioneurotic edema is prohibited, in the process of taking also need to monitor the liver and kidney function and blood pressure, pregnant women and lactating women need to use the drug under the guidance of a doctor. Benadryl belongs to the angiotensin-converting enzyme inhibitor, after taking it can cause the vasopressor activity to reduce, as well as the aldosterone secretion to reduce, so that the serum potassium is mildly increased. It is mainly used in the treatment of hypertension and congestive heart failure. Benadryl may cause dizziness, headache, abdominal pain and other discomforts after administration. It is contraindicated in people who are allergic to the components of the drug, angioneurotic edema. In the course of treatment, it is necessary to monitor electrolytes, blood pressure and liver and kidney functions. Pregnant and lactating women should follow the instructions of the doctor. These two drugs are angiotensin-converting enzyme inhibitors, there is no one better than the other, in the treatment of primary hypertension can choose perindopril, when the response to digitalis or diuretics is not good congestive heart failure can choose Benadryl for treatment. The above drugs need to be standardized under the guidance of a doctor.