Isosorbide mononitrate

About isosorbide mononitrate

Isosorbide mononitrate is used to prevent chest pain which is a symptom of angina and other heart conditions including heart failure (a condition where the pumping action of the heart is reduced).

Angina is pain or tightness of the chest caused by a lack of oxygen reaching the heart muscle. Nitrates like isosorbide mononitrate, work in two different ways. They widen the arteries that carry blood to the heart muscle and they relax the veins that return blood from the body to the heart. Together these actions allow more oxygen to reach the heart muscle and reduce the work of the heart. This lowers the overall strain on the heart reducing the risk of angina and relieving the pain associated with an acute angina attack.

Before taking isosorbide mononitrate

Before taking isosorbide mononitrate make sure your doctor or pharmacist knows:

• If you are pregnant, trying for a baby or breast-feeding.
• If you suffer from a heart condition, liver or kidney problems.
• If you suffer from hypotension (low blood pressure).
• If you have recently suffered a head injury or brain haemorrhage.
• If you have recently suffered a heart attack.
• If you suffer from anaemia (low levels of iron in the blood) or hypoxaemia (low levels of oxygen in the blood).
• If you suffer from thyroid problems.
• If you suffer from glaucoma (increased pressure in the eye).
• If you are taking any products to help treat erectile dysfunction (such as Viagra®).
• If you suffer from hypothermia (low body temperature).
• If you suffer from poor nutrition.
• If you are taking other medicines, including those available to buy without a prescription, herbal or complementary medicines.
• If you have ever had an allergic reaction to this or any other medicine.

How to take isosorbide mononitrate

• Before beginning treatment, read the manufacturer's printed information leaflet.
• Take your medication exactly as directed by your doctor.
• Swallow your tablet or capsule whole. Do not chew or crush it.
• Try to take isosorbide mononitrate at the same times each day to avoid missing any doses.
• If you forget to take a dose, take one as soon as you remember unless it is nearly time for your next dose. Do not take two doses at the same time to make up.

Getting the most from your treatment

• It is best not to drink alcohol while you are taking isosorbide mononitrate as alcohol can make the dizziness you may feel worse. If you do drink alcohol, drink only a little and be aware of its effect on you.
• The longer you take isosorbide mononitrate, the more your body can get used to it which sometimes means it has a lesser effect. To avoid this your doctor may advise that you have some time during each day without isosorbide mononitrate. Follow carefully any instructions you have been given about when to take your doses.
• If you are having any treatment like an operation or dental treatment, tell the person carrying out the treatment which medicines you are taking.
• Keep your regular doctor's appointment so your progress can be monitored.
• Do not stop taking this medicine without speaking to your doctor first.
• If you buy any medicines, check with a pharmacist that they are safe to take with your other medicines.

Can isosorbide mononitrate cause problems?

Along with their useful effects all medicines can cause unwanted side effects, which usually improve as your body adjusts to the new medicine. Speak with your doctor or pharmacist if any of the following side effects continue or become troublesome.

How to store isosorbide mononitrate

• Keep all medicines out of the reach of children.
• Store in a cool, dry place, away from direct heat and light.

Important information about all medicines