What is Nitroglycerin Spray?
Nitroglycerin spray is a fast-acting medication used to treat and prevent chest pain, known as angina, which is often caused by coronary artery disease. It belongs to a class of drugs called nitrates and is administered as a fine mist sprayed onto or under the tongue. The sublingual (under the tongue) method allows for rapid absorption into the bloodstream, enabling the medication to work quickly to alleviate symptoms.
How Nitroglycerin Works
As a vasodilator, nitroglycerin works by relaxing and widening the blood vessels throughout the body, including the coronary arteries that supply the heart muscle. This process has several key effects on the heart:
- Reduces workload: By relaxing the veins, nitroglycerin causes blood to pool in the venous system, reducing the volume of blood returning to the heart. This decreases the heart's workload and its oxygen demand, which helps alleviate anginal pain.
- Increases blood flow: While its primary effect is on the veins, nitroglycerin also dilates the coronary arteries, increasing blood flow and oxygen supply directly to the heart muscle.
When to Use Nitroglycerin Spray
Nitroglycerin spray is used in two main scenarios related to angina:
- Acute attack: At the first sign of chest pain, a person with a prescription can use the spray to quickly treat the attack. It is recommended to sit down immediately before using it to prevent dizziness or fainting due to a potential drop in blood pressure.
- Prophylaxis: For individuals who know that certain activities, such as exercise or emotional stress, may trigger their angina, the spray can be used shortly before the activity to help prevent an attack.
How to Administer the Spray Correctly
Proper use is essential for the medication's effectiveness and safety. Always follow your doctor's specific instructions, but here are the general steps for administering nitroglycerin spray:
- Sit down before administering the spray to prevent injury if you experience dizziness.
- Remove the plastic cap from the container.
- Prime the pump before the first use, or if it hasn't been used recently. Refer to the specific product's instructions for priming procedures.
- Hold the container upright and open your mouth.
- Spray onto or under the tongue. Press the button firmly to release a single spray.
- Close your mouth immediately after spraying. Do not inhale the spray.
- Do not swallow, spit, or rinse your mouth for a short period to allow for proper absorption.
- Repeat as needed. If chest pain persists, additional doses may be taken at intervals recommended by a healthcare professional. However, if the pain does not subside after a specific number of doses within a set timeframe, or if it worsens, seek immediate emergency medical attention by calling 911.
Potential Side Effects and Precautions
Like all medications, nitroglycerin has potential side effects. The most common ones are often related to its vasodilating properties, and can include:
- Headaches
- Dizziness or lightheadedness
- Flushing of the face and neck
- Fast or pounding heartbeat
More serious side effects are rare but require immediate medical attention, such as:
- Rash, blistering, or peeling skin
- Severe low blood pressure (hypotension)
- Pale skin, sweating, or fainting
Contraindications and Drug Interactions
Nitroglycerin is absolutely contraindicated with certain medications, most notably phosphodiesterase-5 (PDE-5) inhibitors used for erectile dysfunction, such as sildenafil (Viagra), tadalafil (Cialis), and vardenafil. The combination can cause a dangerous and potentially fatal drop in blood pressure. Other important contraindications include severe anemia and increased intracranial pressure. Always inform your doctor and pharmacist of all medications and supplements you are taking.
Comparison: Nitroglycerin Spray vs. Tablets
| Feature | Sublingual Tablets (e.g., Nitrostat) | Lingual Spray (e.g., Nitrolingual) |
|---|---|---|
| Speed of Action | Begins working quickly, but generally slower than the spray. | Acts faster due to more rapid absorption through the oral mucosa. |
| Absorption | Can be affected by a dry mouth; requires saliva to dissolve. | Effective even with a dry mouth, as it is a mist. |
| Ease of Use | Requires placing and dissolving a small tablet under the tongue. | A simple, metered-dose spray application. |
| Headache Incidence | Some studies suggest tablets may cause more headaches. | May cause fewer or milder headaches for some users. |
| Stability | Known to lose potency more quickly, especially if not stored properly. | More stable and has a longer shelf life. |
Conclusion
Nitroglycerin spray is an effective and fast-acting treatment for angina associated with coronary artery disease, working as a vasodilator to ease the heart's workload and improve blood flow. Compared to tablets, the spray offers a more rapid onset of action and greater stability. However, it is crucial to use it as directed by a healthcare professional and be aware of potential side effects and drug interactions, particularly with erectile dysfunction medications. Always remember to sit down before use and seek emergency help if symptoms do not improve after the recommended number of doses within the prescribed timeframe.
For more detailed medical information, consult a trusted resource like the NIH website.
