What Does Angina Spray Actually Do? Understanding Nitroglycerin's Role

October 8, 2025 •

4 min read

Angina pectoris, a symptom of coronary artery disease, is a significant health concern worldwide. For individuals experiencing the characteristic chest pain, understanding what does angina spray actually do is crucial for managing acute episodes and obtaining rapid relief.

Quick Summary

Angina spray works by delivering nitroglycerin sublingually, which rapidly dilates blood vessels to decrease the heart's oxygen demand and improve blood flow, thereby relieving angina symptoms.

Key Points

Fast Action: Angina spray delivers nitroglycerin under the tongue for quick absorption and rapid effect, often within minutes.
Vasodilation: The key action is widening of blood vessels, primarily veins and coronary arteries, achieved through the conversion of nitroglycerin to nitric oxide.
Reduces Heart's Workload: By dilating veins, the spray decreases the amount of blood returning to the heart, thus lowering its demand for oxygen.
Increases Blood Flow: Dilation of coronary arteries improves blood flow and oxygen supply directly to the heart muscle.
Acute Relief: It is used to quickly stop an angina attack when chest pain occurs.
Preventative Use: Can be used shortly before activities that are known to trigger angina to help prevent an attack.
Emergency Signal: If pain persists or worsens after taking the spray as directed, it could indicate a more serious condition requiring immediate medical attention.
Drug Interactions: Cannot be used with certain medications, such as PDE-5 inhibitors, due to the risk of severe hypotension.

Understanding Angina

Angina is a type of chest pain, pressure, or discomfort caused by insufficient blood flow to the heart muscle. This usually happens when the coronary arteries, which supply blood to the heart, become narrowed or blocked by plaque buildup, a condition called atherosclerosis. When the heart has to work harder, such as during physical activity or stress, it requires more oxygen. If the narrowed arteries cannot supply enough oxygenated blood, the heart muscle becomes oxygen-deprived, leading to anginal pain.

The Mechanism of Action: Nitroglycerin as a Vasodilator

The primary active ingredient in most angina sprays is nitroglycerin, also known as glyceryl trinitrate. It belongs to a class of medications called nitrates. When administered as a sublingual spray (under the tongue), nitroglycerin is rapidly absorbed into the bloodstream. Its therapeutic effect is due to its conversion into nitric oxide (NO) within the body.

Here’s how this process translates into relief:

Nitric Oxide Production: Nitroglycerin is metabolized to produce nitric oxide, a signaling molecule.
Smooth Muscle Relaxation: Nitric oxide activates an enzyme that leads to the relaxation of smooth muscle cells in the walls of blood vessels.
Blood Vessel Dilation: This relaxation causes the blood vessels to widen, a process known as vasodilation.

The Dual Impact of Vasodilation on Angina

Nitroglycerin's effectiveness in treating angina stems from its dual action on the circulatory system:

Reducing Preload (Workload Reduction): The most significant effect of nitroglycerin is venodilation, the widening of veins. This causes blood to pool in the peripheral veins, reducing the volume of blood returning to the heart. This decreased venous return lowers the pressure and volume within the heart's chambers (preload), which in turn reduces the heart's workload and oxygen demand. By lowering the demand for oxygen, it helps resolve the mismatch between oxygen supply and demand that causes angina.
Improving Coronary Blood Flow (Oxygen Supply): Nitroglycerin also dilates the coronary arteries, including those that are narrowed. This dilation can increase blood flow to the heart muscle, improving oxygen supply and directly addressing the root cause of the pain. It can also help redistribute blood flow to areas of the heart muscle that are not receiving sufficient oxygen.

Proper Use and Administration

Using angina spray correctly is vital for its rapid action. Here are general steps for administration:

Sit Down: When experiencing angina symptoms, sit or lie down immediately to minimize the risk of dizziness from potential blood pressure drop.
Prime the Spray: If it's a new canister or hasn't been used recently, spray a test dose into the air away from your face.
Apply the Spray: Hold the canister upright and spray the medication under or onto your tongue. Avoid shaking the canister.
Close Mouth and Avoid Swallowing: Close your mouth after spraying. Do not inhale the spray or swallow the medication. It's also recommended to avoid eating, drinking, or rinsing your mouth for several minutes to allow for optimal absorption.

When to Seek Emergency Care

If chest pain persists after a certain period or recurs after the initial administration, it is important to follow specific protocols. If the chest pain does not go away after the initial use and recurs, or feels different or worse than usual angina, it is generally recommended to seek emergency medical attention. Follow your doctor's specific instructions on when and how many times to use the spray before calling for help.

Comparing Angina Spray and Sublingual Tablets

Both spray and sublingual tablets deliver nitroglycerin under the tongue for rapid absorption, but there can be differences:


Feature	Angina Spray	Sublingual Tablets
Onset of Action	Typically rapid	Generally rapid, similar to spray
Administration	Sprayed under the tongue	Placed under the tongue to dissolve
Convenience	Can be easier to use, especially with dry mouth	Requires sufficient moisture to dissolve
Stability	Generally considered more stable	Can be sensitive to light, air, and moisture
Packaging	Pressurized canister	Small bottle, often glass

Potential Side Effects and Precautions

Like all medications, nitroglycerin can cause side effects. These are often related to its vasodilating effects.

Common Side Effects: Headaches, flushing (warmth, redness, or tingly feeling under your skin), dizziness, and lightheadedness are frequently reported. These may lessen with continued use.
Serious Side Effects: Seek immediate medical attention if you experience signs of an allergic reaction (hives, difficulty breathing, swelling), severe dizziness, fainting, vision changes, or unusually fast or slow heart rate.
Interactions and Contraindications: Nitroglycerin should not be used by individuals taking certain medications, particularly phosphodiesterase-5 (PDE-5) inhibitors used for erectile dysfunction or pulmonary arterial hypertension (like sildenafil, tadalafil, vardenafil) due to the risk of a severe drop in blood pressure. It is also contraindicated in cases of severe anemia, increased pressure in the brain, and allergy to nitrates. Always inform your doctor about all medications and supplements you are taking.

Conclusion: Rapid Relief for Angina

Angina spray is a vital medication for individuals with angina, providing rapid relief from chest pain by delivering nitroglycerin, a powerful vasodilator, directly into the bloodstream. By converting to nitric oxide, it relaxes blood vessels, decreasing the heart's workload and increasing blood flow to the heart muscle. Understanding how to use the spray correctly, being aware of potential side effects, and knowing when to seek emergency medical help are crucial for effectively managing angina attacks and improving quality of life. This fast-acting treatment is a cornerstone of acute angina management, helping to quickly restore the balance between the heart's oxygen supply and demand.

For further information and resources on angina and heart health, consult your healthcare provider or visit the American Heart Association at www.heart.org.

Frequently Asked Questions

Angina spray is designed for rapid relief, typically working within 1 to 3 minutes after being administered under the tongue, with the maximum effect often seen around 5 minutes.

After spraying under your tongue, close your mouth and avoid swallowing, eating, drinking, or rinsing your mouth for several minutes to allow the medication to be absorbed properly.

If your chest pain does not subside and recurs after using the spray, or feels different or worse than usual, it is important to seek emergency medical attention immediately. Follow your doctor's specific guidance.

Yes, common side effects include headache, dizziness, flushing of the face, and lightheadedness, which are due to the medication's effect of widening blood vessels.

No, it is critically important not to use angina spray if you are taking medications for erectile dysfunction, such as sildenafil or tadalafil, as this combination can cause a dangerous and severe drop in blood pressure.

While both deliver nitroglycerin sublingually, the spray often has a faster onset of action and is considered more stable over time compared to tablets, which can degrade with exposure to light, air, and moisture.

Yes, your doctor may recommend using the spray preventatively 5 to 10 minutes before engaging in activities that you know tend to trigger your angina symptoms, such as exercise.

You should store the spray in its original container at room temperature, away from excessive heat, moisture, and direct sunlight. It is also flammable, so keep it away from open flames.

The main ingredient is nitroglycerin, which works by being converted into nitric oxide in the body, causing relaxation and widening of blood vessels. This reduces the heart's workload and improves blood flow to the heart muscle.