Isosorbide mononitrate and isosorbide dinitrate are types of heart medicine called nitrates. They're similar medicines that work in the same way, but the doses are different, so you'll need to take the type that you're prescribed.
They're used to prevent angina symptoms (chest pain). They do not work to treat a current angina attack.
They're also taken with other medicines to treat heart failure including left ventricular failure.
They work by widening blood vessels and increasing the blood supply to your heart.
Isosorbide mononitrate and isosorbide dinitrate come as tablets or capsules. Isosorbide dinitrate also comes as an injection or drip (infusion), which is given in hospital.
Isosorbide mononitrate and isosorbide dinitrate are only available on prescription.
Key facts
- Isosorbide mononitrate and isosorbide dinitrate tablets and capsules usually start to work within 1 hour.
- Common side effects include headaches and feeling dizzy, weak or tired.
- Do not drive a car or ride a bike if it makes you feel dizzy or tired.
- Drinking alcohol can increase the effects of these medicines, and may make you feel dizzy, lightheaded or sleepy.
- If you're going to have surgery, your doctor may advise you to stop taking isosorbide mononitrate or isosorbide dinitrate. They can lower you blood pressure too much when combined with some anaesthetics.