Isosorbide Mononitrate 10 mg tablets – patient leaflet, side effects, dosage

1. What Isosorbide Mononitrate Tablets are and what they are used for

Isosorbide mononitrate belongs to a group of medicines called organic nitrates.

Organic nitrates work by widening the blood vessels in your heart to allow an increased amount of blood to flow to areas which need it. Isosorbide mononitrate is used to prevent angina pectoris. Angina usually feels like a tight pain in the chest, neck or arm area. The pain comes from the heart muscle and is a sign that part of it is not getting enough oxygen for the amount of work it is doing. Isosorbide mononitrate 20 mg, 30 mg and 40 mg tablets can also be used to treat congestive heart failure. Heart failure can happen when the heart muscle is not strong enough to pump the blood around the body. It may cause problems with breathing and swelling of the legs.

2. What you need to know before you take Isosorbide Mononitrate Tablets

Do not take Isosorbide Mononitrate Tablets:

• if you are allergic to isosorbide mononitrate,

  other nitrates or any of the other ingredients of this medicine (listed in section 6)

• if you suffer from severe anaemia (reduction in

  red blood cells which can make the skin pale and cause weakness or breathlessness)

• if you have had a heart attack (myocardial

  infarction)

• if you have had a brain haemorrhage (bleeding)
• if you have had a head injury (trauma)
• if you have severely low blood volume
• if you have severe low blood pressure

• if you are suffering from ‘shock’ as the blood

  has stopped circulating properly around your body (circulatory failure)

• if you take sildenafil, tadalafil or vardenafil

  (medicines to treat erectile dysfunction and/or pulmonary hypertension) or any other phosphodiesterase inhibitor.

• if you have an eye disease called glaucoma

• if you have been diagnosed with any of the

  following heart conditions: hypertrophic obstructive cardiomyopathy, constrictive pericarditis, cardiac tamponade, low cardiac filling pressures, aortic/ mitral valve stenosis and diseases associated with raised intra-cranial (head) pressure.

• if you are also taking riociguat. See section “other

  medicines and Isosorbide mononitrate tablets” If any of the above applies to you talk to your doctor or pharmacist.

Warnings and precautions

Talk to your doctor or pharmacist before taking Isosorbide mononitrate tablets:

• if you have an underactive thyroid gland

  • if you are malnourished (severely underfed)
  • if you have liver or kidney disease
  • if you suffer from hypothermia (a very low body temperature)
  • if you suffer from very poor circulation
  • if you have abnormally low level of oxygen in the blood and impaired gas exchange due to lung disease or ischaemic heart failure.

Other medicines and Isosorbide mononitrate tablets

• Do not take Isosorbide mononitrate tablets with phosphodiesterase inhibitors such as Sildenafil, Alprostadil, Tadalafil and Vardenafil used for erectile dysfunction. Using Isosorbide mononitrate tablets with these medicines could cause your blood pressure to fall to a dangerously low level. You must not stop taking Isosorbide mononitrate tablets to take these medicines as this will increase your chances of having an angina attack.
• Do not use Isosorbide mononitrate tablets at the same time as riociguat since this can cause hypotension (abnormally low blood pressure). Tell your doctor or pharmacist if you are taking, have recently taken or might take any of the following medicines:
• Medicines to lower your blood pressure such as beta blockers (atenolol, propranolol), calcium channel blockers (nifedipine, diltiazem), vasodilators (glycerol trinitrate, methyldopa), ACE-inhibitors, angiotensin receptor blockers (olmesartan medoxomil, candesartan cilexetil)
• Tricyclic antidepressants such as amitriptyline, clomipramine (used to treat depression)
• Neuroleptics to treat psychosis (delusions, hallucinations and/or disordered thought) such as phenothiazines (fluphenazine) or butyrophenones (haloperidol)
• Ergotamine used for migraine.
• Aldesleukin (for kidney cancer)
• Sapropterine containing medicines for the treatment of abnormally elevated concentration of amino acid phenylalanine in the blood (hyperphenylalaninaemia)
• Any other medicine, including medicines obtained without a prescription.

If any of the above applies to you talk to your doctor. Isosorbide Mononitrate Tablets with alcohol

Do not drink alcohol. It could increase the effect of Isosorbide mononitrate tablets and lower your blood pressure too much. If this happens, you may feel dizzy or faint.

Pregnancy and breast-feeding

If you are pregnant or breast-feeding, think you may be pregnant or planning to have a baby, ask your doctor or pharmacist for advice before taking this medicine. Your doctor will decide whether you should take this medicine.

Driving and using machines

Isosorbide Mononitrate Tablets may give you a headache, blurred vision or make you feel dizzy or tired. If this happens to you, do not drive or operate machinery.

Isosorbide Mononitrate Tablets contain lactose

This medicine contains lactose. If you have been told by your doctor that you have an intolerance to some sugars, contact your doctor before taking this medicinal product.

Information on sodium content

This medicine contains less than 1 mmol sodium (23 mg) per tablet, that is to say essentially ‘sodium-free’

3. How to take Isosorbide Mononitrate Tablets

Always take this medicine exactly as described in this leaflet or as your doctor or pharmacist has told you. Check with your doctor or pharmacist if you are not sure.

Important:

Your doctor will choose the dose that is right for you. Your dose will be shown clearly on the label that your pharmacist puts on your medicine. If it does not, or you are not sure, ask your doctor

50 mm

6 mm

Isosorbide mononitrate 10 mg, 20 mg, 30 mg and 40 mg tablets Package leaflet: Information for the patient

Space for PC

Marketing Authorisation Holder and Manufacturer:

MEDREICH PLC

Warwick House, Plane Tree Crescent, Feltham TW13 7HF, United Kingdom E-mail : info@medreich.co.uk P

This leaflet was last revised in September 2026

To request a copy of this leaflet in Braille, or large print, please call,

020 88311580 (UK only)

Please be ready to give the following information: Product name Reference number

Isosorbide mononitrate PL 21880/0279 10 mg tablets

Isosorbide mononitrate PL 21880/0280 20 mg tablets

Isosorbide mononitrate PL 21880/0281 30 mg tablets

Isosorbide mononitrate PL 21880/0282 40 mg tablets

or pharmacist.

Adults:

• The recommended adult dose is one tablet two

  or three times a day.

• Your doctor will tell you when you should take

  your tablets. You will need to have a period of time (usually when you are sleeping) when no tablets are taken. This is called a “nitrate low” period and is needed to make sure your medicine remains effective.

• Tablets should be taken after meals, swallowed

  whole with water.

• Your doctor may increase your dose, up to a

  maximum of 120 mg per day.

• If you do not take the dose as prescribed by your

  doctor, you may develop a tolerance to Isosorbide mononitrate.

Do not use Isosorbide mononitrate to treat an actual angina attack. Your doctor will give you a different medicine such as a GTN (glyceryl trinitrate) spray or tablet for this.

Use in children

This medicine is not suitable for children. For Isosorbide mononitrate 10mg tablets:

The score line is only there to help you break the tablet if you have difficulty swallowing it whole. For Isosorbide mononitrate 20 mg, 30 mg and 40 mg tablets:

The tablet can be divided into equal doses If you take more Isosorbide mononitrate tablets than you should

Do not take more Isosorbide mononitrate tablets than you should. If you accidentally take too much, immediately contact the nearest hospital casualty department or your doctor.

Too much Isosorbide mononitrate may cause your blood pressure to fall too low, making you feel sick, faint and dizzy. A very large overdose could cause a coma or collapse and require immediate resuscitation. If you forget to take Isosorbide Mononitrate Tablets

Do not take a double dose to make up for a forgotten dose. Take your next dose at the usual time. If you stop taking Isosorbide Mononitrate Tablets

Do not stop taking Isosorbide mononitrate tablets without first talking to your doctor. You should keep taking your medicine until your doctor tells you to stop. Do not stop taking it just because you feel better. If you stop taking the tablets your condition may get worse.

If you have any further questions on the use of this medicine, ask your doctor or pharmacist.

4. Possible side effects

Like all medicines, this medicine can cause side effects, although not everybody gets them. Seek immediate medical help if you are having an allergic reaction. This includes any of the following symptoms:

• Difficulty in breathing
• Swelling of your eyelids, face or lips

• Rash or itching especially those covering your

  whole body

• Collapse
• Fainting
• Serious redness and scaling of the skin

• Worsening angina (tight pain in the chest, neck

  or arm area)

Very common: may affect more than 1 in 10 people

• Headache

Common: may affect up to 1 in 10 people

• Light headedness on standing
• Dizziness
• Sleepiness
• Feeling weak
• Fast heartbeat
• Drowsiness

They may occur for the first few days of treatment or after your dosage has been increased. Uncommon: may affect up to 1 in 100 people

• Fainting or collapse
• Feeling sick or being sick
• Skin rashes
• Looking pale
• Excessive sweating
• Restlessness
• Flushing

Very rare: may affect up to 1 in 10,000 people

• Heartburn

  Other side effects

  • Red or scaly skin (exfoliative dermatitis)
  • Low blood pressure
  • Swelling of the skin

You may also suffer with increased chest pain due to a lack of oxygen to the heart muscle and areas around the chest.

Very slow heart rate has been reported with use of nitrates.

If you experience any symptoms of shock or collapse after first dose, please contact your doctor immediately.

Reporting of side effects

If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects you can help provide more information on the safety of this medicine.

5. How to store Isosorbide Mononitrate Tablets

• Keep this medicine out of the sight and reach of children.
• Do not use this medicine after the expiry date which is stated on the carton and blister pack after EXP. The expiry date refers to the last day of that month.
• This medicinal product does not require any special storage conditions.
• Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.

6. Contents of the pack and other information

What Isosorbide mononitrate tablets contains

The active substance is isosorbide mononitrate. Each tablet contains 10mg, 20mg, 30mg or 40mg of isosorbide mononitrate.

The other ingredients are cellulose microcrystalline, lactose monohydrate, maize starch, silica, colloidal anhydrous, sodium starch glycolate, purified talc and magnesium stearate.

What Isosorbide mononitrate looks like and contents of the pack

10 mg:

White to off white, round tablet, flat with bevelled edge, score & engraving (I/10) on one side and plain on other side. Nominal tablet dimension: 6.35 mm 20 mg:

White to off white, round tablet, flat with bevelled edge, score & engraving (I/20) on one side and plain on other side. Nominal tablet dimension: 8.00 mm 30 mg:

White to off white, round tablet, flat with bevelled edge, score & engraving (I/30) on one side and plain on other side. Nominal tablet dimension: 9.50 mm 40 mg:

White to off white, round tablet, flat with bevelled edge, score & engraving (I/40) on one side and plain on other side. Nominal tablet dimension: 10.50 mm Isosorbide Mononitrate 10 mg, 20 mg, 30 mg and 40 mg Tablets are available in Alu-PVC/PVDC and Alu/PVC blister packs of 28, 30, 56, 60, 84 tablets.

Not all pack sizes may be marketed.

Red 032 C

Unit 3

MED/ISMN/PIL/02

11.08/01.09.26(MA)

Internal Approval issued on CD issued on