How does glyceryl trinitrate work?
Glyceryl trinitrate relaxes and widens blood vessels, which reduces the strain on the heart and improves oxygen delivery to the heart muscle.
What is glyceryl trinitrate used to treat?
Glyceryl trinitrate is commonly prescribed for:
- Angina (chest pain due to reduced blood flow to the heart)
- Preventing angina attacks before exertion
- Heart failure (in some cases, to reduce the workload on the heart)
Who can take glyceryl trinitrate?
Glyceryl trinitrate is suitable for most adults with angina or heart-related conditions, as prescribed by a doctor.
Who might not be able to take glyceryl trinitrate?
Glyceryl trinitrate may not be suitable if you:
- Have very low blood pressure (hypotension)
- Have severe anaemia
- Have a history of recent stroke or head injury
- Are taking medications for erectile dysfunction (such as sildenafil, tadalafil, or vardenafil)
Can I take glyceryl trinitrate if I’m pregnant or breastfeeding?
Glyceryl trinitrate may be used during pregnancy or breastfeeding, but only under medical supervision.
What if I miss a dose?
Glyceryl trinitrate is often used as needed for chest pain, so missing a dose is usually not an issue. If taking a long-acting form, take it as soon as you remember, unless it’s close to your next dose—do not take two doses at once.
How effective is glyceryl trinitrate?
Glyceryl trinitrate is highly effective at relieving angina pain within minutes and preventing chest pain when taken before exertion.
What should I do if I take too much?
Taking too much glyceryl trinitrate can cause severe dizziness, fainting, or dangerously low blood pressure. If you think you’ve taken too much, seek emergency medical help immediately.
What dose of glyceryl trinitrate is usually taken?
- For immediate angina relief: One spray or one tablet under the tongue when chest pain starts (can be repeated after 5 minutes if needed, up to 3 doses in 15 minutes)
- For angina prevention: One spray or tablet before exercise or stressful situations
- For long-term use: Patches or slow-release tablets may be prescribed
Your doctor will determine the correct dose based on your condition.
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What are the side effects of glyceryl trinitrate?
Common side effects include:
- Headache (common in the first few days of treatment)
- Dizziness or lightheadedness
- Flushing (warmth in the face and neck)
- Nausea
Serious side effects, such as severe dizziness, fainting, or signs of an allergic reaction, require urgent medical attention.
How should I take glyceryl trinitrate?
Glyceryl trinitrate is available as sublingual tablets, sprays, patches, and slow-release tablets. Follow your doctor’s instructions carefully.
When should glyceryl trinitrate be taken?
- For chest pain: Take immediately when symptoms start
- For prevention: Take before activities that might trigger angina
- For long-term treatment: Take as prescribed, at the same time each day
What are the brand names for glyceryl trinitrate?
Glyceryl trinitrate is available as a generic medicine, but some branded versions include:
- GTN Spray
- Nitrostat
- Rectogesic (for anal fissures)
Final thoughts
Glyceryl trinitrate is an effective treatment for angina and heart conditions, but it should be taken exactly as prescribed. If side effects occur or angina symptoms do not improve after using GTN, seek medical help immediately.
