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Long-acting nitrates

Long-acting nitrates help prevent angina (chest pain). Read about the types of long-acting nitrates, how they work and their possible side effects.

Types of long-acting nitrates

  • isosorbide mononitrate, also called Imdur, Duride, Ismo, Ismo Retard

How do they work?

Long-acting nitrates help to reduce chest pain (angina). They widen your blood vessels to increase blood flow to the heart. 

Long acting-nitrates are in tablet form and are different to GTN spray. The long-acting tablets prevent chest pain occurring, whereas GTN spray is taken for immediate relief once you have chest pain.

Some people may need more than one medication to achieve these benefits, including beta blockers and calcium channel blockers

Side effects

Long-acting nitrates can cause unwanted side effects such as:

  • headaches
  • flushing
  • dizziness.

Ring 111 if you have any of the following:

  • severe chest pain
  • severe headache
  • acute shortness of breath
  • swelling of your mouth, lips or tongue, as this could be an allergic reaction. 

Talk to your doctor if your side effects are worrying you. Don’t stop taking your medication without talking to your doctor first. The benefit usually outweighs the side effects.

Long-acting nitrates can be used with GTN spray.

What happens if I miss a dose?

It's important to take your medication daily and not to skip a dose. 

If you forget to take a dose, take it immediately, then continue as normal the following day. However, if it’s almost time for the next dose, skip the missed dose and continue as normal. 

Do NOT take a double dose.

What else do I need to know?

Tell your health professionals if you're taking any:

  • supplements
  • natural medicines
  • vitamins
  • alternative therapies.

These can sometimes make your heart medication less effective. 

Do not take long-acting nitrates if you're taking medicines for difficulties with erections, such as:

  • sildenafil (Viagra, Avigra, Vedafil, Silvasta)
  • tadalafil (Cialis)
  • vardenafil (Levitra).

Using these medications together can cause a drop in blood pressure and is not recommended.

Talk to your doctor if you’re planning to get pregnant or are breastfeeding.

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