If you have been diagnosed with hypertension and have been prescribed lisinopril, you may wonder how quickly it will work.
In this article, I’ll start by explaining what lisinopril is, how it works, and how fast it works to lower blood pressure.
I’ll then list some of the medication’s potential side effects. I’ll tell you who can take lisinopril—and who can’t.
I’ll provide some warnings for this medication, and tell you when you should talk to a doctor or primary care provider about your blood pressure or your medication.
What Is Lisinopril and What Does It Do?
Angiotensin II is a hormone produced in your body that narrows the arteries.
When your arteries become more narrow, your blood pressure increases—just as water will flow with more pressure through a narrower pipe than it does through a wider one.
Lisinopril is a type of blood pressure medication called an angiotensin-converting enzyme inhibitor, or ACE inhibitor.
These medications help the body produce less angiotensin II.
By blocking angiotensin II, blood pressure levels decrease as blood vessels dilate, improving blood flow, and more fluids are released.
Lisinopril is sold under the brand name Zestril.
It is mostly used for hypertension, but it may also be prescribed for managing heart failure, heart attack prevention, stroke prevention, and complications associated with diabetic kidney disease.
How to take it
Lisinopril may be prescribed as a tablet or a liquid.
It is commonly taken once daily and is best taken at the same time each day.
Your prescription insert will contain instructions on how to take it. Read it thoroughly.
Lisinopril dosages can range from 5-40 mg, depending on the reason it is prescribed.
The most common dosage is between 10-40 mg per day.
Your health care provider may start you on a low dose and adjust it upward as needed.
If your lisinopril prescription is in liquid form, use the syringe that came with your medication to ensure accurate measurement.
Do not use a spoon or a measuring device that is not meant for your medication.
Lisinopril may not make you feel differently when you start taking it, but that does not mean it isn’t working.
High blood pressure does not typically cause symptoms, so treating it likely will not change how you generally feel.
Your provider will closely monitor your blood pressure as you adjust to taking lisinopril.
This will ensure that you are receiving the right dosage and that your blood pressure is responding to treatment.
When to take it
A common side effect of starting lisinopril is dizziness.
Your provider may recommend taking your first dose before bed, but once your body is used to it, it can be taken at any time of day.
Take your dose at the same time each day so that you remember to take it as part of your daily routine.
If you miss a dose of lisinopril, do not take a double dose.
Take it as soon as you remember and resume your normal, once-daily dose.
Does Lisinopril Lower Blood Pressure Quickly?
Lisinopril can start to lower blood pressure within an hour, and reaches peak effectiveness within 6 hours of taking your first dose.
If your dose is 20 mg or higher, the effects are likely to be more noticeable.
It may take 2-4 weeks for overall blood pressure levels to stabilize into the optimal range.
Potential Side Effects
Fewer than 6% of people needed to change medications due to side effects with lisonipril, according to clinical trial research.
Some common side effects include:
If you experience dizziness that lingers consistently after your first dose, let your provider know.
The dry cough that lisinopril causes is not treatable with cough suppressants.
If you develop a dry cough that is problematic, talk to your healthcare provider.
If any of your symptoms feel severe or impact your quality of life, let your doctor or provider know.
In rare cases, lisinopril may cause serious side effects. If you experience any of the following, call 9-1-1 right away:
- Swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
- Chest pain
- Light-headedness or fainting
- Breathing problems
- Trouble swallowing
- Chills or fever
- Yellowing of the skin or eyes
Who Can Take Lisinopril?
Lisinopril is FDA-approved for people ages 6 and older.
Like other medications, lisinopril may interact with certain prescriptions, supplements, or herbs.
Tell your doctor and pharmacist about everything that you take, even if it is over-the-counter or a supplement.
If you are trying to get pregnant, tell your doctor or provider.
Some research indicates that ACE inhibitors are not safe in the second and third trimesters of pregnancy.
Your provider may recommend a different medication if you are trying to conceive or might be pregnant.
Who Can’t Take Lisinopril?
Lisinopril is not safe under certain circumstances.
These may include:
- Pregnancy and breastfeeding
- While taking the medication aliskiren (Tekturna) for diabetes
- Having a history of angioedema (swelling of the throat, face, or limbs)
- Syndrome of inappropriate antidiuretic hormone secretion (SIADH)
- Imbalanced electrolytes
- Kidney disease, kidney failure, or dialysis
- Low neutrophils, a type of white blood cell
- Hypertrophic cardiomyopathy
- Low blood pressure
- Abnormal liver function
- Decreased blood volume
Lisinopril is excreted via the urine, so people who have kidney disorders or other kidney problems may experience severe side effects or health problems.
People who are Black may not respond as well to Lisinopril according to the FDA.
Other medications, such as diuretics, may be required to produce effective results.
Only take your medication as prescribed.
Do not adjust your own dosage or give leftover medication to anyone else.
Discard unused medication properly.
If you are not sure how to discard unused prescription medications, ask your doctor or pharmacist, or follow the FDA’s advice for safely discarding prescriptions that are no longer needed.
If you take too much medication, get help at PoisonHelp.org or call Poison Control at 1-800-222-1222.
When to See a Doctor
You should see a doctor if you have concerns about how well your blood pressure medication is working, or if you are experiencing side effects.
How K Health Can Help
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Frequently Asked Questions
K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.
K Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references.
Zestril (lisinopril). (n.d.).
Taking ACE inhibitors during early pregnancy. (2007).
Where and how to dispose of unused medicines. (2021).
Treatment of Hypertension with Combination of Lisinopril/Hydrochlorothiazide. (2016).