Lisinopril can begin lowering blood pressure within hours of the first dose, but you might not feel any different when you’re on the medication.
Here’s what you should know about taking lisinopril, including how quickly it lowers blood pressure.
How Quickly Does Lisinopril Lower Blood Pressure?
Lisinopril, commonly sold under the brand name Zestril, begins to lower blood pressure within six hours of the first dose being administered. This is true with all doses, although adults who are on a dose of at least 20 milligrams (mg) have more consistent results and a more significant drop in blood pressure.
Research has also shown that Black individuals can be slightly less responsive to lisinopril than other populations. As such Black individuals may be prescribed additional medications, such as a diuretic, to improve effectiveness.
Although lisinopril acts quickly, it can take two to four weeks for your blood pressure to drop into the target range. Because of this, it’s important to continue taking lisinopril as prescribed, even if you don’t feel any different when you’re taking it.
High blood pressure is dangerous, but it doesn’t usually cause any noticeable symptoms. Your healthcare provider will bring you in for regular blood pressure checks, especially as your body adjusts to lisinopril. This ensures that the medication is doing what it should.
You can also talk to your healthcare provider about monitoring your blood pressure at home, but this is generally considered less effective than having a professional check your blood pressure.
If you do monitor your blood pressure at home, be sure that you’re following guidelines, including sitting properly, measuring at the same time each day, and avoiding exercise, caffeine, and smoking 30 minutes before you measure your blood pressure.
What Does Lisinopril Do?
Lisinopril’s main function is to lower blood pressure. Like other ACE inhibitors, lisinopril stops the production of the hormone angiotensin II, which causes the blood vessels to narrow and fluids to be retained. Those two processes can result in hypertension, so when angiotensin II is blocked, blood pressure decreases. This improves blood flow and allows the heart to pump more effectively.
Lisinopril primarily treats high blood pressure, but it is also used for:
Heart failure treatmentHeart attack prevention and improving survival rate after a heart attackStroke preventionDiabetic kidney disease treatment
Lisinopril isn’t metabolized in the body, but it is excreted in the urine.
The first dose of lisinopril can cause dizziness, so doctors say bedtime is the best time of day to take the first dose. After that, you can take lisinopril any time. It is common for people to start on a low dose of lisinopril, and gradually increase the dose with time, under the guidance of their healthcare provider.
Common Lisinopril Side Effects
It’s common for the first dose of lisinopril to cause dizziness. If that happens once, don’t be concerned. However, if it happens consistently, you should contact your healthcare provider.
Generally, lisinopril is well tolerated. In clinical trials, less than 6% of people discontinued the medication due to side effects.
Common side effects of lisinopril include:
Dry cough Dizziness Headache Fatigue Nausea and diarrhea Sneezing or runny nose Rash Decreased libido
It’s important to note that an ACE inhibitor–induced dry cough can happen within hours of the first dose to months after you start the therapy. The cough will not be alleviated with over-the-counter (OTC) cough suppressants, but it may stop after a while. Let your healthcare provider know about the dry cough.
There are also rare but serious side effects. If you experience any of the following, you should call your healthcare provider or 911 immediately:
Swelling Difficulty breathing or swallowingHoarsenessFever or chillsYellow-tinged skin or eyesLight-headedness or faintingChest pain
Who Can Take Lisinopril?
Lisinopril is approved for people ages 6 and up. In most cases, lisinopril cannot be taken by people who are:
Pregnant or breastfeedingHave a history of angioedema, or swelling of the face, throat, or limbsHave diabetes and are taking the medication Tekturna (aliskiren)
As you decide whether lisinopril is right for you, be sure to tell your healthcare provider about the following:
All medications, herbs, and supplements that you take, as lisinopril can interact with some medications Any recent or upcoming surgeriesAny medical procedures like dialysisAny recent bouts of diarrhea or vomitingAny dietary restrictions, including being on a low-salt dietIf you are trying to get pregnant
A Word From Verywell
For most people, lisinopril is a safe, effective, and well-tolerated medication that can help lower blood pressure within two to four weeks. Talk to your healthcare provider about other steps that you can take to help lower blood pressure, including exercising, changing your diet, and quitting smoking. Be sure to speak with your healthcare provider regarding any concerns you have about lisinopril, and inform your provider of all other medications you are on.