Table of ContentsView AllTable of ContentsHow They WorkTypesUsesAdministrationSide EffectsInteractions
Table of ContentsView All
View All
Table of Contents
How They Work
Types
Uses
Administration
Side Effects
Interactions
Vasodilatorsare a class of medication that dilate arteries and/or veins. This results in increased blood flow and lowered blood pressure. Vasodilators are commonly used to treathigh blood pressure(hypertension) and heart conditions.
This article discusses vasodilators and their uses, administration, and side effects.
kate_sept2004 / Getty Images
How Do Vasodilators Work?
Vasodilators relax the muscles within blood vessel walls so they remain more widely open. The various classes of vasodilators target different pathways to dilate the blood vessel walls buthave the same overall effect: lowering blood pressure and improving blood flow.
Types of Vasodilators
Vasodilators may target the arteries, veins, or both. They may act directly on the blood vessel wall or indirectly through other pathways.
Nitrovasodilators
Nitrovasodilatorsincludenitrates(chemical compounds containing nitrogen and oxygen), likenitroglycerine,isosorbide dinitrateandisosorbide, andsodium nitroprusside.
Nitrates work on veins and are used to treat heart conditions likeangina,heart attacks, andheart failure. Sodium nitroprusside acts on both veins and arteries and is used to treat hypertensive emergencies and heart failure.
Direct Acting Arterial Vasodilators
HydralazineandMinoxidilare direct-acting vasodilators that preferentially dilate arteries. They are not the first-choice treatment for hypertension but may be used with other medications to treat resistant hypertension.
Indirect Arterial Vasodilators
Some examples of indirect arterial vasodilators include:
Indications for Using Vasodilators
Based on their specific properties, individual vasodilators have different uses. Vasodilators are most commonly prescribed to treat the following conditions.
High Blood Pressure
The vasodilators that are more specific to arteries are used totreat high blood pressure. These include calcium channel blockers, RAAS blockers, hydralazine, and minoxidil.
Hydralazine and minoxidil are not first-line therapies, but they are used in combination with other medications to treat high blood pressure that has not been responsive to other treatments.
Angina and Heart Attack
Nitroglycerin and the long-acting nitrate medication isosorbide mononitrate are used in thetreatment of angina, which is chest pain related to narrowing of the coronary arteries.Nitrates dilate veins and coronary arteries to improve blood flow to the heart.
Pulmonary Hypertension
Phosphodiesterase inhibitors and endothelin receptor antagonists are types of vasodilators used in the treatment of pulmonary hypertension (PH). They dilate blood vessels in the lungs to lower the elevated blood pressure in PH.
Vasodilators can be given in various forms:
Tachyphylaxis in NitratesOne important thing to note about nitrovasodilators is the concept oftachyphylaxis. Over time, the body develops tolerance to nitrates, and higher and higher doses are required to achieve the same effect. To avoid this, a nitrate-free period is built into the administration. For example, if you are prescribed a nitrate patch, you may be told to remove it overnight to avoid developing tachyphylaxis.
Tachyphylaxis in Nitrates
One important thing to note about nitrovasodilators is the concept oftachyphylaxis. Over time, the body develops tolerance to nitrates, and higher and higher doses are required to achieve the same effect. To avoid this, a nitrate-free period is built into the administration. For example, if you are prescribed a nitrate patch, you may be told to remove it overnight to avoid developing tachyphylaxis.
As a drug class, vasodilators can cause several side effects, some of which may be serious. These can include:
Additional Side EffectsDifferent vasodilators each have their own specific side effects beyond those mentioned. If you are experiencing new symptoms after starting a vasodilator, be sure to discuss them with your healthcare provider.
Additional Side Effects
Different vasodilators each have their own specific side effects beyond those mentioned. If you are experiencing new symptoms after starting a vasodilator, be sure to discuss them with your healthcare provider.
Vasodilators have a few important drug interactions.
High Blood Pressure and Erectile Dysfunction: What to Know
Summary
Common side effects of vasodilators include dizziness and headache. Severe side effects can include anaphylaxis and fainting. Combining vasodilators can result in severe blood pressure drops.
A Word From Verywell
8 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.American Heart Association.Types of blood pressure medications.Whelton PK, Carey RM, Aronow WS, et al.2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: a report of the American College of Cardiology/American Heart Association task force on clinical practice guidelines.Hypertension. 2018;71:e13–e115. doi:10.1161/HYP.0000000000000065Messerli F, Bangalore S, Bavishi C, et al.Angiotensin-converting enzyme inhibitors in hypertension.J Am Coll Cardiol.2018;71(13):1474-1482. doi:10.1016/j.jacc.2018.01.058Halpern DG, Weinberg CR, Pinnelas R, Mehta-Lee S, Economy KE, Valente AM.Use of medication for cardiovascular disease during pregnancy: JACC state-of-the-art review.J Am Coll Cardiol.2019;73(4):457-476. doi:10.1016/j.jacc.2018.10.075MedlinePlus.Isosorbide.American Lung Association.Treating and managing pulmonary arterial hypertension.MedlinePlus.Nitroglycerin.American Heart Association.Sex and heart disease.
8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.American Heart Association.Types of blood pressure medications.Whelton PK, Carey RM, Aronow WS, et al.2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: a report of the American College of Cardiology/American Heart Association task force on clinical practice guidelines.Hypertension. 2018;71:e13–e115. doi:10.1161/HYP.0000000000000065Messerli F, Bangalore S, Bavishi C, et al.Angiotensin-converting enzyme inhibitors in hypertension.J Am Coll Cardiol.2018;71(13):1474-1482. doi:10.1016/j.jacc.2018.01.058Halpern DG, Weinberg CR, Pinnelas R, Mehta-Lee S, Economy KE, Valente AM.Use of medication for cardiovascular disease during pregnancy: JACC state-of-the-art review.J Am Coll Cardiol.2019;73(4):457-476. doi:10.1016/j.jacc.2018.10.075MedlinePlus.Isosorbide.American Lung Association.Treating and managing pulmonary arterial hypertension.MedlinePlus.Nitroglycerin.American Heart Association.Sex and heart disease.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
American Heart Association.Types of blood pressure medications.Whelton PK, Carey RM, Aronow WS, et al.2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: a report of the American College of Cardiology/American Heart Association task force on clinical practice guidelines.Hypertension. 2018;71:e13–e115. doi:10.1161/HYP.0000000000000065Messerli F, Bangalore S, Bavishi C, et al.Angiotensin-converting enzyme inhibitors in hypertension.J Am Coll Cardiol.2018;71(13):1474-1482. doi:10.1016/j.jacc.2018.01.058Halpern DG, Weinberg CR, Pinnelas R, Mehta-Lee S, Economy KE, Valente AM.Use of medication for cardiovascular disease during pregnancy: JACC state-of-the-art review.J Am Coll Cardiol.2019;73(4):457-476. doi:10.1016/j.jacc.2018.10.075MedlinePlus.Isosorbide.American Lung Association.Treating and managing pulmonary arterial hypertension.MedlinePlus.Nitroglycerin.American Heart Association.Sex and heart disease.
American Heart Association.Types of blood pressure medications.
Whelton PK, Carey RM, Aronow WS, et al.2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: a report of the American College of Cardiology/American Heart Association task force on clinical practice guidelines.Hypertension. 2018;71:e13–e115. doi:10.1161/HYP.0000000000000065
Messerli F, Bangalore S, Bavishi C, et al.Angiotensin-converting enzyme inhibitors in hypertension.J Am Coll Cardiol.2018;71(13):1474-1482. doi:10.1016/j.jacc.2018.01.058
Halpern DG, Weinberg CR, Pinnelas R, Mehta-Lee S, Economy KE, Valente AM.Use of medication for cardiovascular disease during pregnancy: JACC state-of-the-art review.J Am Coll Cardiol.2019;73(4):457-476. doi:10.1016/j.jacc.2018.10.075
MedlinePlus.Isosorbide.
American Lung Association.Treating and managing pulmonary arterial hypertension.
MedlinePlus.Nitroglycerin.
American Heart Association.Sex and heart disease.
Meet Our Medical Expert Board
Share Feedback
Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit
Was this page helpful?
Thanks for your feedback!
What is your feedback?OtherHelpfulReport an ErrorSubmit
What is your feedback?
