Names & Terms You Will Hear
Plain-language meanings for the terms your care team may use.
| Term | Meaning |
|---|---|
| Nitrate | A family of heart medicines that relax and widen blood vessels to ease and prevent chest pain (angina). |
| Nitroglycerin (Nitrostat, Nitrolingual, Nitro-Dur, NitroMist) | The best-known nitrate. Comes as a fast under-the-tongue tablet or spray, and as a long-acting skin patch. |
| Sublingual | Means 'under the tongue.' The fast tablet or spray is placed there so it works in minutes. |
| Isosorbide dinitrate / isosorbide mononitrate (Isordil, Imdur) | Long-acting nitrate pills taken every day to PREVENT angina. |
| Long-acting nitrate | A pill or skin patch that works for many hours to keep angina away. |
| Nitrate-free interval | A planned gap each day with no nitrate in the body. It keeps the medicine from losing its effect. |
| Nitrate tolerance | When a nitrate slowly stops working because the body is exposed to it around the clock. The daily gap prevents this. |
| Angina | Chest pain or pressure that happens when the heart muscle does not get enough blood. Nitrates are a main treatment. |
Shown in English for your safety — this section is not automatically translated. Confirm with your doctor or call the office.
The most important safety rule: never take any nitrate with an erectile-dysfunction drug — sildenafil (Viagra), tadalafil (Cialis), or vardenafil. Together they can drop your blood pressure to a deadly level. And during an attack: if chest pain is severe, or is not better after one dose under the tongue, call 911 right away — do not wait it out.What Is Nitrates?
- Nitrates are some of the oldest heart medicines. Nitroglycerin has been used for chest pain for more than 140 years.
- They turn into a natural gas in the body called nitric oxide. This signals blood vessels to relax and widen.
- When vessels widen, less blood crowds back into the heart and the heart pumps against less pressure. So the heart needs less oxygen.
- Because the heart works less hard, the squeezing chest pain of angina eases or is prevented.
- Nitrates do not open blocked arteries or cure heart disease. They ease the heart's workload and relieve symptoms.
- They come in two main roles: a FAST form to stop an attack, and a LONG-acting form to prevent attacks. The next sections explain each.
Why It Matters
- Angina can limit what you do every day. Nitrates can stop an attack within minutes and let you get back to your activity.
- Carrying fast-acting nitroglycerin gives you a safe, proven tool the moment chest pain starts.
- Long-acting nitrates lower how often angina strikes, so many people walk farther and do more with less pain.
- Guidelines (the 2023 AHA/ACC chronic coronary disease guideline) list long-acting nitrates as a core medicine to prevent angina.
- Nitrates work well alongside beta-blockers and other heart medicines. See our beta-blockers guide below.
- Knowing how to use the fast dose — and when to call 911 — can save your life if chest pain turns out to be a heart attack.
Role 1 — Fast-Acting: To STOP an Attack
- This is the under-the-tongue tablet (like Nitrostat) or the mouth spray (like Nitrolingual or NitroMist).
- It works within minutes. You use it the moment chest pain (angina) starts — not every day.
- Carry it with you at all times so it is ready when you need it.
- Sit down before you take it, because it can make you lightheaded.
Role 2 — Long-Acting: To PREVENT Attacks
- This is a daily pill (isosorbide, such as Imdur or Isordil) or a skin patch (such as Nitro-Dur).
- You take it on a set schedule to keep angina from starting — not to treat an attack already happening.
- It needs a daily nitrate-free gap (often overnight, or patch off for part of the day) so it keeps working.
- It is often used together with a beta-blocker or other heart medicines. See our beta-blockers guide.
Risk Factors
Knowing your personal risks helps your care team take extra precautions.
| Risk Factor | Why It Increases Risk |
|---|---|
| You have stable angina from coronary artery disease | Nitrates are a main treatment — a fast dose for attacks and often a long-acting dose to prevent them. |
| Your angina is limiting your daily activity | A long-acting nitrate, added to other medicines, can lower how often angina strikes. |
| You take an erectile-dysfunction drug (sildenafil, tadalafil, vardenafil) | This is a reason NOT to take nitrates. The combination can cause a dangerous drop in blood pressure. |
| You have very low blood pressure or severe aortic valve narrowing | Nitrates may not be safe. Your doctor will weigh this carefully before prescribing them. |
Treatment Options
Shown in English for your safety — this section is not automatically translated. Confirm with your doctor or call the office.
- For an attack: stop, sit down, and place ONE fast dose under your tongue. Let it dissolve — do not chew or swallow it.
- Wait about 5 minutes. If the pain is severe, or it is not better after that one dose, call 911 right away. Do not wait it out.
- While you wait for help, you may take up to two more doses, one every 5 minutes (three doses total) — but call 911 first.
- To prevent angina, a long-acting pill or skin patch is taken every day on a set schedule your doctor gives you.
- Long-acting nitrates need a daily nitrate-free gap (often overnight, or patch off for part of the day). This keeps them working.
- Store fast-acting nitroglycerin in its original dark glass bottle, tightly closed, away from heat and light. It can lose strength over time.
- Tablets often last only a few months after the bottle is opened. Replace them as your pharmacist or label directs so they work when you need them.
- Never take any nitrate with an erectile-dysfunction drug. Tell your doctor about every medicine and supplement you use.
Nitrate Forms — Which One Does What
| Form | Examples | When it is used | How fast it works |
|---|---|---|---|
| Under-the-tongue tablet | Nitrostat | To STOP an attack | Within minutes |
| Mouth spray | Nitrolingual, NitroMist | To STOP an attack | Within minutes |
| Long-acting pill | Isosorbide (Imdur, Isordil) | To PREVENT attacks | Hours; taken daily |
| Skin patch | Nitro-Dur | To PREVENT attacks | Hours; worn part of the day |
How To Use the Fast Dose During an Attack
- Step 1: Stop what you are doing and sit down to rest.
- Step 2: Place ONE dose under your tongue (or use one spray). Let it dissolve — do not swallow it.
- Step 3: Wait about 5 minutes. If the pain is gone, rest a while longer before getting up.
- Step 4: If the pain is severe, or is not better after that one dose, CALL 911 now. You may take up to two more doses, 5 minutes apart, while you wait for help.
- If you are not sure whether it is angina or a heart attack, treat it as an emergency and call 911. See our chest pain guide.
Comfort Measures at Home (No Medication Needed)
These simple steps support healing and ease symptoms. Use them alongside any medication your doctor prescribes.
- Sit or lie down before taking a dose. Nitrates can make you lightheaded, and sitting lowers the chance of a fall.
- Stand up slowly afterward. Rise from sitting or lying in two steps to avoid dizziness.
- A headache after a dose is common and usually fades. A plain acetaminophen (Tylenol) often helps — ask us first.
- Keep your fast-acting nitroglycerin with you at all times, and check the expiration date so a fresh supply is ready.
- Take long-acting nitrates at the same times each day so the daily nitrate-free gap stays in place.
- Avoid alcohol around a dose. It can add to the drop in blood pressure and make you dizzy.
Risks, Benefits, and Alternatives
Shown in English for your safety — this section is not automatically translated. Confirm with your doctor or call the office.
Every choice has trade-offs. Use this table to start the shared decision conversation with your care team.
| Option | Risks | Benefits | Alternatives |
|---|---|---|---|
| Fast-acting nitroglycerin (under the tongue or spray) for an angina attack | Headache, flushing, lightheadedness, low blood pressure. Sit down before each dose. | Stops most angina attacks within minutes. A safe tool to carry and use the moment pain starts. | Rest alone for mild pain. If pain does not ease quickly, the alternative is to call 911 for emergency care. |
| Long-acting nitrate (pill or skin patch) to prevent angina | Headache (often eases over days), lightheadedness, losing effect without a daily nitrate-free gap. | Fewer angina attacks; many people do more with less chest pain. A core preventive medicine. | Beta-blockers, calcium channel blockers, or ranolazine — alone or added. See our beta-blockers guide. |
| Adding a nitrate to other anti-anginal medicines | More chance of low blood pressure or dizziness when combined with other blood-pressure-lowering drugs. | Better symptom control when one medicine is not enough. | A procedure to open the artery (a stent) or bypass surgery for the right patients. See our CAD guide. |
Common Misconceptions
| Myth | Reality |
|---|---|
| Nitroglycerin unblocks my arteries. | It does not. Nitrates widen blood vessels and lower the heart's workload, which eases pain. They do not clear out the blockage. Opening a blockage takes a stent or surgery. |
| If one dose under the tongue does not work, I should keep taking doses and wait. | No. Modern advice is to call 911 if the pain is severe or is not better after one dose. Do not wait through all three doses before getting help — it could be a heart attack. |
| I can take my nitroglycerin and my erectile-dysfunction pill if I just space them apart. | This is dangerous. Nitrates and drugs like sildenafil (Viagra), tadalafil (Cialis), or vardenafil must NEVER be combined. Together they can drop your blood pressure to a deadly level. Tell every doctor you take a nitrate. |
| My nitroglycerin lasts for years in the bottle. | It can lose strength, especially once the bottle is opened or exposed to heat and light. Keep it in its dark glass bottle and replace it as directed so it works when you need it. |
| A headache means the nitrate is harming me. | Headache is the most common side effect and usually means the medicine is working. It often fades over days. Tell us if it is severe or does not settle. |
| I can take my long-acting nitrate around the clock for the best protection. | Around-the-clock use actually makes nitrates stop working (tolerance). A planned nitrate-free gap each day is what keeps them effective. |
| Nitrates are addictive. | They are not addictive. But a long-acting nitrate should not be stopped suddenly — talk with us before any change. |
Possible Complications
Knowing what can go wrong helps you spot problems early. Most complications are uncommon, especially with treatment.
| Where / What | What Can Happen |
|---|---|
| Blood pressure | Nitrates can lower blood pressure too much, causing lightheadedness or fainting, especially when standing. Sit down before each dose and rise slowly. |
| Head and skin | Headache and facial flushing are the most common effects. Headache usually eases over days; acetaminophen often helps. |
| Drug interaction — erectile-dysfunction drugs | Combined with sildenafil (Viagra), tadalafil (Cialis), or vardenafil, nitrates can cause a severe, even fatal, drop in blood pressure. This combination is never allowed. |
| Losing effect (tolerance) | Around-the-clock nitrate exposure makes the medicine stop working. A daily nitrate-free gap prevents this. |
| Rare effects | Fast heartbeat, blurred vision, or a rare blood problem (methemoglobinemia) can occur. Call us for severe or unusual symptoms. |
| Stopping suddenly | A long-acting nitrate should not be stopped abruptly, which could trigger more angina. Change it only with your doctor. |
Points to Know
Shown in English for your safety — this section is not automatically translated. Confirm with your doctor or call the office.
If you remember nothing else, remember these key points.
- Nitrates relax and widen blood vessels so the heart works less and chest pain eases.
- Fast-acting nitroglycerin (under the tongue or spray) STOPS an attack; long-acting pills or patches PREVENT attacks.
- During an attack: stop, sit, take one dose. If pain is severe or not better after one dose, call 911.
- Never combine nitrates with erectile-dysfunction drugs (sildenafil, tadalafil, vardenafil) — it can cause a deadly drop in blood pressure.
- Long-acting nitrates need a daily nitrate-free gap to keep working.
- Headache and lightheadedness are common; sit down before each dose.
- Store fast-acting nitroglycerin in its dark bottle and replace it as directed — it can lose strength.
- Tell every doctor, dentist, and pharmacist that you take a nitrate.
When to Call Us — and When to Call 911
Shown in English for your safety — this section is not automatically translated. Confirm with your doctor or call the office.
If you are not sure, call. We would rather hear from you twice than miss a real problem.
- Chest pain that is severe, or not better after one dose under the tongue — call 911.
- Chest pain with sweating, nausea, or pain spreading to the arm, jaw, or back — call 911.
- You took a nitrate after an erectile-dysfunction drug and feel faint, very dizzy, or have a pounding heartbeat — call 911.
- Fainting or near-fainting after a dose — call 911 if you do not wake quickly; otherwise call us today.
- A headache after your nitrate that is severe or will not settle — call us.
- Your fast-acting nitroglycerin does not seem to work or has expired — call us for a fresh supply.
- You need angina relief more often than usual, or with less activity — call us this week; your plan may need to change.
- You are starting any new medicine and are not sure if it is safe with a nitrate — call us before you take it.
Office: (727) 943-5200
Trusted Resources
Independent, evidence-based pages we recommend for deeper reading.
- American Heart Association — Angina (Chest Pain) — Patient-friendly overview of angina and how nitroglycerin relieves it.
- Cleveland Clinic — Nitroglycerin Tablets — How to take the fast and long-acting forms, side effects, and the drug-interaction warning.
- MedlinePlus — Nitroglycerin Sublingual — NIH/NLM plain-language instructions for safe dosing, storage, and warnings.
- Our Stable Angina Guide — What angina is and the full plan to control it, including nitrates.
- Our Chest Pain Guide — How to tell apart kinds of chest pain and when it is an emergency.
- Our Coronary Artery Disease Guide — The blocked-artery disease behind most angina, and how we treat it.
- Our Beta-Blockers Guide — Another core anti-anginal medicine often used together with nitrates.
Sources Used to Build This Guide
- American Heart Association — Angina (Chest Pain) [patient_education] — Plain-language role of nitroglycerin in relieving angina, how/when to take sublingual doses, and the call-911 rule if pain persists.
- Cleveland Clinic — Nitroglycerin Tablets [patient_education] — Covers sublingual, patch, and long-acting nitrate forms, headache/low-BP side effects, and the PDE5-inhibitor interaction warning.
- MedlinePlus — Nitroglycerin Sublingual [patient_education] — NIH/NLM drug monograph for safe dosing, storage, nitrate-free interval to prevent tolerance, and contraindications.
- MedlinePlus — Isosorbide Mononitrate [patient_education] — NIH/NLM monograph for the long-acting nitrate used to PREVENT angina, including the daily dose-spacing that builds in a nitrate-free interval.
- Mayo Clinic — Nitroglycerin (Oral/Sublingual Route) [patient_education] — Patient-facing dosing and precautions, the sit-down-before-dosing tip, and the dangerous interaction with erectile-dysfunction drugs.
- 2023 AHA/ACC/ACCP/ASPC/NLA/PCNA Guideline for the Management of Patients With Chronic Coronary Disease [guideline] — Current guideline basis for long-acting nitrates as anti-anginal therapy, the need for a nitrate-free interval to avoid tolerance, and the PDE5 contraindication.
- FDA Label — Nitrostat (Nitroglycerin Sublingual Tablets) [drug_label] — Official prescribing information: sublingual dosing for an attack, the call-for-help timing, storage to preserve potency, and the absolute PDE5-inhibitor contraindication.
- FDA Label — Imdur (Isosorbide Mononitrate Extended-Release) [drug_label] — Prescribing information for the long-acting nitrate, including the once-daily dosing schedule designed to provide a nitrate-free interval and limit tolerance.
- AHA Scientific Statement — Sexual Activity and Cardiovascular Disease (PDE5 inhibitor + nitrate interaction) [guideline] — Authoritative statement that PDE5 inhibitors (sildenafil, tadalafil, vardenafil) are contraindicated with nitrates because of severe, potentially fatal low blood pressure.
- StatPearls (NIH NCBI Bookshelf) — Nitroglycerin [reference] — Mechanism (nitric oxide donor causing vein and artery widening that lowers the heart's workload and oxygen need), the tolerance mechanism, and the PDE5 interaction.
- American Heart Association — Cardiac Medications [patient_education] — Places nitrates among the heart medicines and frames their role in relieving and preventing angina alongside beta-blockers and other anti-anginals.
