isosorbide dinitrate at a glance
Medicine class
Organic nitrate and vasodilator
Main tablet uses
Preventing angina and, for standard tablets, treating symptoms of congestive heart failure
Sudden angina attack
Oral tablets do not act quickly enough to treat an attack that has already started
Available forms
Standard and prolonged-release tablets; injection or infusion is administered in hospital
What is isosorbide dinitrate used for?
Licensed uses vary by formulation.
Standard tablets: prevention of angina and treatment of congestive cardiac failure.
Prolonged-release tablets: prevention and treatment of angina; they are not suitable for rapid relief of an acute attack.
Hospital injection or infusion: selected acute cardiac conditions and prevention or relief of coronary spasm during angioplasty.
How does isosorbide dinitrate work?
It releases nitric oxide, relaxing blood vessels. This reduces blood returning to the heart and can reduce arterial resistance, lowering the heart’s workload and oxygen demand.
isosorbide dinitrate preparations and strengths
Tablet
Route: Oral
Strengths: 10 mg, 20 mg
Injection
Route: Parenteral
Strengths: 1 mg/mL, 0.05% w/v, 0.1% w/v
How to take isosorbide dinitrate
Standard and prolonged-release tablets are not interchangeable.
Swallow tablets with water.
Swallow prolonged-release tablets whole; do not chew them.
Tablets may be taken with or without food. Taking them after food may help nausea.
isosorbide dinitrate side effects
Common or expected effects
- Headache, especially when treatment begins
- Dizziness or light-headedness, particularly on standing
- Tiredness, weakness or sleepiness
- Feeling sick or vomiting
- Flushing
- Fast heartbeat or palpitations
Get urgent medical advice
- Severe allergic reaction with facial or throat swelling or breathing difficulty
- Very low blood pressure causing pallor, sweating, fainting or collapse
- Angina that becomes worse
- Markedly fast or slow heartbeat
- Severe eye pain with blurred vision or sudden loss of sight
- Severe blistering or peeling skin reaction
isosorbide dinitrate in pregnancy
It can be used in pregnancy when clinically needed, but only when the expected benefit outweighs possible risk. Pregnancy should prompt early review by the prescriber, an obstetrician and a cardiology team.
isosorbide dinitrate while breastfeeding
Breastfeeding may be possible if the infant is healthy, following discussion with a doctor or pharmacist. Transfer into milk is uncertain, so caution is advised. Seek advice if the infant feeds poorly, gains insufficient weight, is unusually sleepy or becomes irritable.
isosorbide dinitrate interactions
Review all prescribed, non-prescribed and complementary products because combined blood-vessel widening can cause clinically important low blood pressure.
PDE-5 inhibitors, including sildenafil, tadalafil, vardenafil and avanafil
Do not combine: blood pressure may fall dangerously, causing collapse or life-threatening cardiovascular effects.
Riociguat
Concurrent use is contraindicated because it can cause excessive hypotension.
Antihypertensives and other vasodilators
Combined effects may increase dizziness, postural hypotension and fainting.
Common questions about isosorbide dinitrate
Answers are fully visible for fast scanning and source review.
Can it stop an angina attack that has already started?
Oral tablets are not fast enough for immediate relief. Follow the separate action plan and rescue treatment provided for acute angina.
Can prolonged-release tablets be crushed or chewed?
No. They must be swallowed whole.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.