Nitroglycerin is a medication used to alleviate chest pain, known as angina, which arises from coronary artery disease. This condition occurs when blood flow to the heart muscle is restricted, often due to narrowed arteries. Nitroglycerin, a type of nitrate, helps by relaxing and widening blood vessels throughout the body. This process, called vasodilation, increases the supply of blood and oxygen to the heart while simultaneously reducing the heart’s overall workload.
Immediate Relief and Its Duration
When experiencing chest pain, nitroglycerin provides rapid relief, beginning its effect within one to five minutes for sublingual tablets or sprays. Maximum benefit is observed within five to seven minutes after administration. This quick action helps restore blood flow to the heart muscle during an angina attack.
The pain-relieving effects of sublingual nitroglycerin last for about 30 to 60 minutes. To take this medication, it is recommended to sit down, as it can cause a sudden drop in blood pressure, leading to dizziness or lightheadedness. Placing the tablet under the tongue or spraying it onto or under the tongue allows for quick absorption into the bloodstream.
Take one dose at the first sign of chest pain. If pain does not subside, another dose may be taken five minutes later. This can be repeated for a total of up to three doses within a 15-minute period. Following these instructions is important to manage symptoms.
Maintaining Nitroglycerin’s Effectiveness Over Time
The effectiveness of nitroglycerin depends on its proper storage, as the medication is sensitive to light, heat, and moisture. Exposure to these elements can degrade the active ingredient, making the medication less potent and ineffective when needed. Therefore, careful storage ensures the medication remains effective.
Nitroglycerin tablets should be kept in their original amber-colored glass bottle, which protects them from light. The cap must be screwed on tightly after each use to prevent exposure to air and moisture. The ideal storage temperature is room temperature, between 20°C and 25°C (68°F and 77°F), away from direct sunlight and humidity. Avoid storing nitroglycerin in places like bathrooms, where humidity levels can fluctuate, or in the refrigerator.
While older recommendations suggested discarding tablets three to six months after opening, modern formulations are more stable. If stored correctly in temperate environments, the medication can maintain potency until its printed expiration date. However, improper storage can still lead to a loss of effectiveness within a few months, so check product-specific instructions and replace the medication if it is past its expiration date or its potency is questionable.
When to Seek Medical Attention
Recognize when chest pain indicates a more serious condition requiring immediate medical attention, even after taking nitroglycerin. If chest pain does not improve or worsens after taking the maximum recommended three doses within a 15-minute period, emergency medical help is needed. Persistent chest pain could signal a heart attack or another cardiac event.
Medical attention is also needed if new symptoms develop, such as shortness of breath, pain radiating to other parts of the body, or severe dizziness and fainting. These symptoms, along with a drop in blood pressure, indicate the heart may not be receiving sufficient oxygen. In such situations, immediately call emergency services, like 911, and avoid driving yourself to the hospital.