Vasodilators

What are vasodilators?

Vasodilators are medicines that dilate (open) your blood vessels. Vasodilators keep your arteries and veins from narrowing or contracting (squeezing) shut.

You have two main types of blood vessels. Veins carry blood to your heart, while arteries carry blood from your heart to the rest of your body.

What is vasodilation?

Vasodilation is blood vessel widening (or getting bigger). It occurs when the muscles in your blood vessel walls relax. When you take a vasodilator, the blood vessel’s middle interior (lumen) is the part that widens.

How do vasodilator drugs work?

There are several types of vasodilator medications, and they all work slightly differently. Direct vasodilators directly affect the muscle cells that line your blood vessels. They make your muscle cells relax so that blood vessels open. Because they work quickly, they can cause more side effects. Healthcare providers use direct vasodilators when other treatments haven’t worked.

Other vasodilators control the chemicals that make your blood vessels expand or contract. They are effective but work more slowly.

What are the types of vasodilator drugs?

Types of vasodilators include:

• Angiotensin-converting enzyme (ACE) inhibitors decrease ACE enzymes. Decreasing ACE enzymes lowers angiotensin. Angiotensin is a chemical that causes blood vessel constriction (narrowing). ACE inhibitors are direct vasodilators.
• Angiotensin receptor blockers (ARBs) keep angiotensin from attaching to your blood vessel walls. Preventing this attachment opens your blood vessels. ARBs are indirect vasodilators, not direct vasodilators.
• Calcium channel blockers (CCBs) prevent calcium from going into your artery walls. Your arteries use calcium for constriction, so blocking calcium leads to artery opening. CCBs are systemic vasodilators, not direct vasodilators.
• Nitrates convert to a gas called nitrous oxide. Nitrous oxide activates specific chemicals that help open your blood vessels. Nitrates are direct vasodilators.

What do vasodilators treat?

Healthcare providers may prescribe vasodilators to treat conditions that affect blood flow, including:

• Angina (chest pain caused by decreased blood flow).
• Congestive heart failure (CHF).
• High blood pressure (hypertension).
• Preeclampsia (hypertension during pregnancy).
• Postpartum preeclampsia (hypertension after childbirth).
• Pulmonary hypertension (hypertension that affects arteries in your lungs).

What are the most common vasodilator medications?

There are many vasodilator drugs. Your provider will recommend a medication that is right for you, depending on the underlying condition. You may need to try several types to find the right one.

A list of common vasodilators includes:

• ACE inhibitors such as benazepril (Lotensin®) or lisinopril (Prinivil®, Zestril®).
• ARBs such as losartan (Cozaar®).
• CCBs such as diltiazem (Cardizem®, Tiazac®).
• Other direct vasodilators such as hydralazine (Apresoline®), minoxidil (Loniten®) or nitroglycerin (Nitrostat®).

What are the benefits of using vasodilators?

Vasodilators can be very effective for people with certain heart conditions. They are widely used treatments for high blood pressure.

Opening your blood vessels can:

• Improve blood flow through your heart.
• Reduce pressure in your blood vessels or on your heart.
• Send more oxygen to your heart.

What are the risks of using vasodilators?

Direct vasodilators are strong medicines. Typically, healthcare providers only prescribe them when other treatments have failed to control symptoms.

Direct vasodilators may cause more severe side effects than other types of vasodilators. Sometimes, these side effects are severe enough that you need other medicines to treat the side effects. For example, a vasodilator may cause water retention, which can raise pressure and lead to congestive heart failure. You may need to take a diuretic to help your body release the additional fluid.

Some types of vasodilators cause more severe effects, and the effects can vary from person to person. You and your provider may need to try several medicines to find one that works well with the fewest side effects. When you take vasodilators, you may have:

• Dizziness.
• Dry cough (with ACE inhibitors).
• Edema (fluid retention).
• Fatigue.
• Headaches.
• Joint pain.
• Heart palpitations or rapid heartbeat (tachycardia).
• Nausea and vomiting.

Are there natural vasodilators?

Vasodilators are not the only way to open blood vessels. Some other factors that cause vasodilation include:

• Exercise: When you exercise, your blood vessels open so that your muscles can get extra nutrients and oxygen.
• Inflammation: Inflammation is part of your body’s process of repairing the damage. When a part of your body is inflamed, your blood vessels dilate to send more oxygen and nutrients to that area.
• Natural chemicals: Your body releases some chemicals naturally that can encourage vasodilation. Some examples of these chemicals include carbon dioxide, nitric oxide and the hormone prostaglandin.
• Alcohol: Drinking alcohol causes blood vessel dilation. This is why some people get flushed, warm skin after drinking alcohol. It’s especially common with alcohol intolerance.

Some herbs or supplements can also help with vasodilation. Some supplements have adverse medication reactions, so speak with your provider before taking any herb or supplements. Vasodilator supplements may include:

• Cocoa.
• Coenzyme Q10 (CoQ10).
• Garlic.
• L-arginine.
• Magnesium.
• Niacin (vitamin B3).

What medication interactions should I watch for?

Ask your provider about possible food or drug interactions if you are taking vasodilators. It’s important to be honest and thorough when telling your provider what medications or supplements you take.

Some vasodilator interactions to watch for include:

• ACE inhibitors and potassium supplements.
• ACE inhibitors and medications with lithium.
• ARBs and ACE inhibitors.
• CCBs and grapefruit juice.
• CCBs and verapamil (Calan®, Isoptin®) and diltiazem (Cardizem®).
• Nitrates and sildenafil (Viagra®), tadalafil (Cialis®) and vardenafil (Levitra®).

How long should I take vasodilators?

How long you need to take vasodilators depends on what condition the medicine is treating. For example, if you take vasodilators to treat preeclampsia, you may stop taking the drug after you give birth. But if you have a chronic condition such as pulmonary hypertension, your provider may keep you on vasodilators long-term.

Sometimes, you can manage chronic conditions through lifestyle changes. For example, you may lower your blood pressure by losing weight and exercising regularly. Your provider will monitor any chronic conditions and guide your treatment options.

Who should not use vasodilators?

Vasodilators are not right for everyone. Ask your cardiologist (heart doctor) if you are a good candidate for vasodilator drugs. Generally, you may not be able to take certain types of vasodilators if you are pregnant or have:

• History of angioedema.
• Mitral valve rheumatic heart disease.
• Right ventricular infarction.
• Severe hypersensitivity or hypotension (low blood pressure).

Are vasodilators the only heart treatment I need?

For most people, vasodilators are one part of an overall heart treatment plan. You can keep your heart healthier by adopting healthy lifestyle habits. You may:

• Achieve and maintain a healthy weight.
• Avoid secondhand smoke or quit smoking.
• Drink alcohol in moderation only.
• Eat a nutrient-dense diet full of vegetables, fruits and whole grains.
• Exercise aerobically for at least 150 minutes per week.
• Manage stress with healthy strategies, such as meditation or talk therapy.

A note from Cleveland Clinic

Vasodilators are medications that open your blood vessels. Your healthcare provider may prescribe vasodilators to treat certain heart conditions, such as high blood pressure or CHF. Although vasodilators work well, they may cause some side effects. Tell your provider if you have dizziness, fatigue or headaches. You might take vasodilators short-term. Or you may need to keep taking the medication to manage a long-term condition.