Zestril (lisinopril) is an oral ACE inhibitor medication that is prescribed for the treatment of congestive heart failure and high blood pressure for adults as well as children above the age of six years old. Zestril may be used alongside other medications or by itself.
How is Zestril Used?
Zestril is a tablet that is taken once per day, with or without food, to manage a patient’s high blood pressure. Based on a variety of individual factors, a patient’s dosage and instructions regarding taking the medication may vary. Patients should be sure to take their medication exactly as directed by their prescribing physician.
Zestril should be stored in a container that is tightly sealed and kept away from moisture, and it should be kept at room temperature in a range between 68°F (20°C) and 77°F (25°C).
Keep this medication out of the reach of children at all times.
Zestril is prescribed for the treatment of high blood pressure and may also be used for patients with congestive heart failure, particularly after a patient has just experienced a heart attack.
Zestril may also be prescribed off-label to assist in the management of the following conditions:
- diabetic kidney disease
- diabetic retinopathy
- heart disease
- male infertility
- mitral valve regurgitation
How Does Zestril Work?
Zestril is an ACE inhibitor, meaning that it hinders a person’s angiotensin-converting enzymes, preventing the body from converting angiotensin I into angiotensin II. Angiotensin II causes increased fluid retention and blood pressure due to the fact that it handles both stimulation of a person’s adrenal cortex as well as vasoconstriction. When Zestril inhibits the enzymes responsible for converting angiotensin I into angiotensin II, this reduces the overall level of angiotensin II within the body and reduces the amount of fluid retention an individual experiences and lowers their blood pressure.
It may take up to two weeks for its full effects to become evident despite the fact that it begins working within hours after being consumed.
Zestril is available in tablet form and comes in the following strengths:
- 5 mg
- 10 mg
- 20 mg
The specific dosage a patient will be required to take each day varies based on the specific condition that is being treated. Some individuals may only need 2.5 mg per day to manage their symptoms, yet others may take up to 40 mg each day.
Children requiring treatment with Zestril will have their dosage determined by their weight. Those who already take medications that lower their blood pressure will typically be prescribed a lower dose, including those who take diuretics and those who may have kidney disease. Other factors may also impact the required dose for effective treatment, and patients using Zestril should take the medication exactly as prescribed by their doctor.
Consuming too much of a medication that lowers a patient’s blood pressure can be life-threatening and even fatal if the individual who has overdosed does not seek immediate medical attention. If you or another patient has consumed too much Zestril or suspect that an overdose has occurred, emergency medical attention should be sought immediately.
Zestril is associated with a variety of different side effects. Serious side effects should be reported to the patient’s prescribing physician as soon as possible. If a patient using Zestril experiences any side effects that appear to be life-threatening, emergency medical attention should be sought immediately.
The most common side effects of taking Zestril are as follows:
- chest pain
- low blood pressure
- persistent cough
Some of the following more serious side effects may also occur and should be discussed with your doctor immediately if you are taking Zestril:
- allergic reaction
- abdominal pain (may be accompanied by vomiting or nausea)
- difficulty breathing
- difficulty swallowing
- swelling of the throat, tongue, lips, or face
- hypokalemia (high potassium levels)
- arrhythmia symptoms
- excessively low blood pressure
- liver failure
- elevated liver enzymes
- stomach pain
- kidney problems
- shortness of breath
- swelling of the feet, ankles, or hands
- weight gain
- pancreatitis symptoms
- abdominal swelling
- back pain
- pain in the upper left of your abdomen
- racing heart
- severe skin reaction
- fever that accompanies a rash
- quick-spreading rash
- a rash that covers a significant amount of the body
Please contact your doctor for further information if you experience any of the following additional side effects and have any concerns.
- anemia symptoms
- changes in sexual performance
- changes in taste
- clotting issues (e.g., nosebleeds, bleeding gums, bleeding that won’t stop, etc.)
- difficulty sleeping
- dry mouth
- flu-like symptoms
- hair loss
- rapid heartbeat
- runny nose
- skin rash
- unusual dreams
Warnings & Precautions
Zestril is associated with a number of potential risks and serious side effects. Please be sure to discuss your medical history and all current health conditions and medications with your physician before beginning treatment.
Zestril is associated with some patients using the medication experiencing angioedema, the swelling of the individual’s tongue or throat associated with an allergic reaction. If a patient experiences any symptoms of an allergic reaction while using Zestril, the medication should be stopped immediately, and emergency medical attention should be sought as soon as possible. These individuals should also avoid using any similar medications in the future due to an increased risk of allergic reactions.
Zestril may sometimes cause leukopenia, or a low white blood cell count, in patients using the medication. Low levels of white blood cells increase a patient’s risk of developing infections, and this may potentially lead to serious complications. Patients using Zestril who exhibit symptoms of an infection should consult with their physician as soon as possible.
It has not been determined if Zestril is both safe and effective for children below the age of six years. Zestril has been used in children above the age of six years but is not recommended for those younger than this.
Some patients using Zestril have developed a persistent dry cough that is resolved only by lowering their dosage of the medication or stopping Zestril entirely. If a patient is using Zestril and develops an unusual cough that has no clear cause, they should discuss this with their doctor.
Individuals with diabetes that use Zestril for treatment are at an increased risk of experiencing hypoglycemia (low blood glucose levels). Diabetic patients should be sure to discuss this diagnosis with their physician before beginning treatment with Zestril to ensure they receive the appropriate dosage of the medication to avoid complications.
Zestril is associated with a reduction in patients’ liver function as well as the development of liver failure. Those who are using Zestril and experience jaundice, fatigue, nausea, itchy skin, abdominal swelling or pain, loss of appetite, pale stools, or dark urine should immediately inform their prescribing physician. Patients with preexisting liver issues should be sure to inform their doctor of any relevant medical history and current conditions or symptoms, as these may affect the efficacy of Zestril and the required dosage for treatment.
Hypotension (Low Blood Pressure)
Significant drops in blood pressure sometimes occur when a patient first begins using Zestril or increases their dosage for the first time. Individuals that use aliskiren or diuretics, have vomiting or diarrhea, eat a diet with restricted salt intake, are dehydrated from excessive sweating, or are on dialysis have a much higher risk of experiencing unusually low blood pressure in these cases. If you experience symptoms of overly low blood pressure and any of the prior conditions apply to you, please contact your prescribing physician.
Zestril is known to cause changes in a patient’s kidney function. This risk is higher in patients using Zestril that have severe congestive heart failure, narrowed blood vessels within their kidneys, or that use the following medications: aliskiren, nonsteroidal anti-inflammatory medications, or diuretics. Patients with preexisting kidney impairment or disease should be sure to discuss these conditions with their doctor before beginning treatment with Zestril. Often, these individuals will be prescribed a lower dosage of Zestril for treatment.
Pregnancy and Breastfeeding
Zestril is not safe for use during pregnancy as it poses a severe threat to the well-being and life of an unborn, developing child. Zestril also passes into breast milk and should not be used by patients that are breastfeeding due to the risks this medication poses to any infant consuming the patient’s breast milk.
If a patient requires any surgical procedure that uses general anesthesia, they should be sure to notify their care team (especially their doctor and anesthesiologist) of any Zestril use before undergoing such a procedure. Anesthesia is known to interact with some blood pressure medications, and this can result in complications related to sedation. Typically, a patient undergoing surgery will be requested to stop using it for a certain time period before receiving general anesthesia.
Speak to your doctor about any medications or herbal supplements you are currently taking before beginning treatment with Zestril. Discuss any concerns you may have with your doctor or a trusted pharmacist.
Drugs That Are Known to Interact with Zestril
The following medications are known to interact with Zestril:
- angiotensin-converting enzyme (ACE) inhibitors
- angiotensin receptor blockers
- anti-Parkinson’s medications
- antipsychotic medications
- beta-adrenergic blockers
- calcium channel blockers
- diabetes medications
- grass pollen allergen extract
- iron (dextran complex, gluconate, and sucrose)
- isosorbide dinitrate
- isosorbide mononitrate
- low-molecular-weight heparins
- mood stabilizers
- neprilysin inhibitors
- NSAIDs (nonsteroidal anti-inflammatory drugs)
- oral diabetes drugs
- pain medications
- phosphodiesterase-5 inhibitors
- potassium supplements
- renin inhibitors
- sodium aurothiomalate (injectable gold)
- sodium phosphates
- tricyclic antidepressants
For patients who are unable to take Zestril or experiencing significant adverse side effects, alternative medications may be used to treat some of the associated conditions for which this medication is commonly prescribed:
- aliskiren (Tekturna)
- amlodipine (Norvasc)
- amlodipine/benazepril (Lotrel)
- amlodipine/valsartan (Exforge)
- amlodipine/olmesartan (Azor)
- amlodipine/telmisartan (Twynsta)
- amlodipine/hydrochlorothiazide/olmesartan (Tribenzor)
- amlodipine/hydrochlorothiazide/valsartan (Exforge HCT)
- atenolol (Tenormin)
- benazepril (Lotensin)
- bisoprolol/hydrochlorothiazide (Ziac)
- candesartan (Atacand)
- carvedilol (Coreg)
- carvedilol, extended-release (Coreg CR)
- clonidine (Catapres)
- clonidine patch (Catapres TTS)
- diltiazem, extended-release (Cardizem CD)
- doxazosin (Cardura)
- enalapril (Vasotec)
- felodipine XR
- furosemide (Lasix)
- hydrochlorothiazide/aliskiren (Tekturna HCT)
- hydrochlorothiazide/benazepril (Lotensin HCT)
- hydrochlorothiazide/candesartan (Atacand)
- hydrochlorothiazide/captopril (Capozide)
- hydrochlorothiazide/enalapril (Vaseretic)
- hydrochlorothiazide/irbesartan (Avalide)
- hydrochlorothiazide/losartan (Hyzaar)
- hydrochlorothiazide/olmesartan (Benicar HCT)
- hydrochlorothiazide/quinapril (Accuretic)
- hydrochlorothiazide/telmisartan (Micardis HCT)
- hydrochlorothiazide/valsartan (Diovan HCT)
- irbesartan (Avapro)
- labetalol (Trandate)
- lisinopril/hydrochlorothiazide (Zestoretic)
- losartan (Cozaar)
- metoprolol (Lopressor)
- metoprolol, extended-release (Toprol XL)
- nebivolol (Bystolic)
- nifedipine, extended-release (Nifedical XL)
- olmesartan (Benicar)
- propranolol extended release (Inderal LA)
- quinapril (Accupril)
- ramipril (Altace)
- spironolactone (Aldactone)
- telmisartan (Micardis)
- valsartan (Diovan)
- verapamil extended release (Calan SR)