Consumer medicine information

APO-Isosorbide Mononitrate Sustained-Release Tablets

Isosorbide mononitrate

BRAND INFORMATION

Brand name

APO-Isosorbide Mononitrate

Active ingredient

Isosorbide mononitrate

Schedule

S4

 

Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using APO-Isosorbide Mononitrate Sustained-Release Tablets.

SUMMARY CMI

APO-ISOSORBIDE MONONITRATE

Consumer Medicine Information (CMI) summary

The full CMI on the next page has more details. If you are worried about using this medicine, speak to your doctor or pharmacist.

1. Why am I using APO-ISOSORBIDE MONONITRATE?

APO-ISOSORBIDE MONONITRATE contains the active ingredient Isosorbide mononitrate. APO-ISOSORBIDE MONONITRATE is used to prevent angina pectoris (heart pain). It is not recommended and should not be taken for the treatment of acute attacks.

For more information, see Section 1. Why am I using APO-ISOSORBIDE MONONITRATE? in the full CMI.

2. What should I know before I use APO-ISOSORBIDE MONONITRATE?

Do not use if you have ever had an allergic reaction to APO-ISOSORBIDE MONONITRATE or any of the ingredients listed at the end of the CMI.

Talk to your doctor if you have any other medical conditions, take any other medicines, or are pregnant or plan to become pregnant or are breastfeeding.

For more information, see Section 2. What should I know before I use APO-ISOSORBIDE MONONITRATE? in the full CMI.

3. What if I am taking other medicines?

Some medicines may interfere with APO-ISOSORBIDE MONONITRATE and affect how it works.

A list of these medicines is in Section 3. What if I am taking other medicines? in the full CMI.

4. How do I use APO-ISOSORBIDE MONONITRATE?

  • Your Doctor will advise you on how many tablets to take each day.

More instructions can be found in Section 4. How do I use APO-ISOSORBIDE MONONITRATE? in the full CMI.

5. What should I know while using APO-ISOSORBIDE MONONITRATE?

Things you should do
  • Remind any doctor, dentist or pharmacist you visit that you are using APO-ISOSORBIDE MONONITRATE.
  • Tell your doctor if you continue to have angina attacks or if they become more frequent while you are using APO-ISOSORBIDE MONONITRATE
Things you should not do
  • Do not use it to treat any other complaints unless your doctor says to.
  • Do not give this medicine to anyone else, even if their symptoms seem similar to yours
Driving or using machines
  • Be careful driving or operating machinery until you know how APO-ISOSORBIDE MONONITRATE affects you. This medicine may cause tiredness, dizziness or light-headedness in some people.
Drinking alcohol
  • Be careful when drinking alcohol while using APO-ISOSORBIDE MONONITRATE
  • If you drink alcohol while using APO-ISOSORBIDE MONONITRATE, your blood pressure may drop, making you feel dizzy or faint.
Looking after your medicine
  • Store below 25°C.
  • Store in a cool, dry place away from young children.

For more information, see Section 5. What should I know while using APO-ISOSORBIDE MONONITRATE? in the full CMI.

6. Are there any side effects?

Possible side effects include headache (most common), dizziness, nausea, tiredness and disturbed sleep.

For more information, including what to do if you have any side effects, see Section 6. Are there any side effects? in the full CMI.



FULL CMI

APO-ISOSORBIDE MONONITRATE

Active ingredient(s): Isosorbide mononitrate


Consumer Medicine Information (CMI)

This leaflet provides important information about using APO-ISOSORBIDE MONONITRATE. You should also speak to your doctor or pharmacist if you would like further information or if you have any concerns or questions about using APO-ISOSORBIDE MONONITRATE.

Where to find information in this leaflet:

1. Why am I using APO-ISOSORBIDE MONONITRATE?
2. What should I know before I use APO-ISOSORBIDE MONONITRATE?
3. What if I am taking other medicines?
4. How do I use APO-ISOSORBIDE MONONITRATE?
5. What should I know while using APO-ISOSORBIDE MONONITRATE?
6. Are there any side effects?
7. Product details

1. Why am I using APO-ISOSORBIDE MONONITRATE?

APO-ISOSORBIDE MONONITRATE contains the active ingredient Isosorbide mononitrate. APO-ISOSORBIDE MONONITRATE is belongs to a group of medicines called nitrates. It works by widening blood vessels to improve the blood flow around the heart which means there is more oxygen being carried by the blood. This reduces the pain associated with angina.

APO-ISOSORBIDE MONONITRATE is used to prevent angina pectoris (heart pain).

Angina is a pain or uncomfortable feeling in the chest, often spreading to the arms or neck and sometimes to the shoulders and back. This may be caused by too little blood and oxygen getting to the heart. The pain of angina is usually brought on by exercise or stress.

2. What should I know before I use APO-ISOSORBIDE MONONITRATE?

Warnings

Do not use APO-ISOSORBIDE MONONITRATE if:

  • you are allergic to isosorbide mononitrate, or any of the ingredients listed at the end of this leaflet, or any medicine or food containing nitrites.
  • Always check the ingredients to make sure you can use this medicine.
  • You are pregnant or intend to become pregnant.
  • You are breast feeding or intend to breast feed. Isosorbide passes into breast milk. The effect on the baby is unknown.
  • If you are in a state of shock including shock caused by very low blood pressure due to a failing heart, have hypotension (low blood pressure), weakened muscle of the heart or pericarditis (swelling around the heart).
  • You are having an acute angina attack. They should be taken once daily.
  • you are not sure whether you should start taking APO-ISOSORBIDE MONONITRATE, contact your doctor.
  • you are a child.
    The safety and effectiveness of Isosorbide has not been established in children.
  • you are taking any of the following phosphodiesterase type 5 inhibitors,
    - Sildenafil
    - Tadalafil
    - Vardenafil

Check with your doctor if you:

  • have any other medical conditions, especially heart, liver or kidney failure
  • take any medicines for any other condition.
  • you suffer from low blood pressure or blood vessel disease such as hardening of the arteries.

During treatment, you may be at risk of developing certain side effects. It is important you understand these risks and how to monitor for them. See additional information under Section 6. Are there any side effects?

Pregnancy and breastfeeding

Do not take if pregnant or intend to become pregnant, or if you are breastfeeding or intend to breastfeed.

Check with your doctor if you are pregnant or intend to become pregnant.

Talk to your doctor if you are breastfeeding or intend to breastfeed.

Isosorbide may affect your developing baby if you take it during pregnancy.

Isosorbide passes into breast milk. The effect on the baby is unknown.

3. What if I am taking other medicines?

Tell your doctor or pharmacist if you are taking any other medicines, including any medicines, vitamins or supplements that you buy without a prescription from your pharmacy, supermarket or health food shop.

Some medicines may interfere with APO-ISOSORBIDE MONONITRATE and affect how it works.. These medicines include:

  • Sildenafil (Viagra®), Tadalafil and Vardenafil may cause fainting or heart attacks
  • N-acetylcysteine or captopril with Isosorbide may result in a prolonged anti-angina effect.
  • calcium channel blocker of the verapamil type may improve heart function. However, the combination of Isosorbide with any other calcium channel blocker may cause hypotension (low blood pressure) requiring dose adjustment of either medicine
  • betablocker medicines such as propranolol may cause hypotension (low blood pressure).

You may need to take different amounts of your medicine, or you may need to take different medicines. Your doctor will advise you.

Check with your doctor or pharmacist if you are not sure about what medicines, vitamins or supplements you are taking and if these affect APO-ISOSORBIDE MONONITRATE.

4. How do I use APO-ISOSORBIDE MONONITRATE?

How much to take / use

  • Your doctor will advise you on how many tablets you should take
  • Follow the instructions provided and use APO-ISOSORBIDE MONONITRATE until your doctor tells you to stop.

When to take / use APO-ISOSORBIDE MONONITRATE

  • Food does not affect the absorption of isosorbide so the tablets may be taken with or without food.
  • Follow all directions given to you by your doctor and pharmacist carefully.
  • These directions may differ from the information contained in this leaflet.
  • If you do not understand the instructions on the packaging, ask your doctor or pharmacist for help.

If you forget to use APO-ISOSORBIDE MONONITRATE

APO-ISOSORBIDE MONONITRATE should be used regularly at the same time each day. If you miss your dose at the usual time, take it as soon as you remember unless more than eight hours have passed.

If more than eight hours have passed since the time the dose should have been taken, do not take the missed dose but take the next dose at the normal time.

A missed dose may lead to an angina attack that in turn may need medication, prescribed by your doctor, capable of treating an acute attack such as use of immediate release tablets or spray administered under the tongue.

APO-ISOSORBIDE MONONITRATE is not recommended and should not be taken for the treatment of acute angina attacks.

Do not take a double dose to make up for the dose you missed.

If you use too much APO-ISOSORBIDE MONONITRATE

If you think that you have used too much APO-ISOSORBIDE MONONITRATE, you may need urgent medical attention.

If you take too much APO-Isosorbide mononitrate, the most common symptom is a pulsing headache. More serious symptoms are excitation, flushing, cold sweats, nausea, vomiting, vertigo, increased heart beat and a fall in blood pressure.

You should immediately:

  • phone the Poisons Information Centre
    (by calling 13 11 26), or
  • contact your doctor, or
  • go to the Emergency Department at your nearest hospital.

You should do this even if there are no signs of discomfort or poisoning.

5. What should I know while using APO-ISOSORBIDE MONONITRATE?

Things you should do

Use APO-ISOSORBIDE MONONITRATE exactly as your doctor has prescribed.

If you do not follow your doctor's instructions, you may not get relief from your attacks of angina.

Call your doctor straight away if you:

  • continue to have angina attacks or if they become more frequent while you are using APO-ISOSORBIDE MONONITRATE

Remind any doctor, dentist or pharmacist you visit that you are using APO-ISOSORBIDE MONONITRATE.

Things you should not do

  • Do not give this medicine to anyone else, even if their symptoms seem similar to yours.
  • Do not use it to treat any other complaints unless your doctor says to.

Things you should be careful of

Be careful not to overdo physical activities when you first start using APO-ISOSORBIDE MONONITRATE.

You may feel better when you start taking it, but you will need time to improve your physical fitness.

Get up slowly when getting out of bed or standing up if you feel light-headed, dizzy or faint.

You may feel light-headed or dizzy when you begin to take Isosorbide or if the dose is increased. This is because your blood pressure is falling suddenly. Standing up slowly, especially when you get up from bed or chairs, will help your body get used to the change in position and blood pressure. The problem usually goes away after the first few days.

If this problem gets worse or continues, talk to your doctor.

Driving or using machines

Be careful before you drive or use any machines or tools until you know how APO-ISOSORBIDE MONONITRATE affects you.

APO-ISOSORBIDE MONONITRATE may cause dizziness, tiredness or light headedness in some people.

Drinking alcohol

Tell your doctor if you drink alcohol.

Alcohol may cause your blood pressure to drop making you feel dizzy or faint.

Looking after your medicine

  • Keep your tablets in a cool dry place. APO-ISOSORBIDE MONONITRATE should be stored below 25°C

Follow the instructions in the carton on how to take care of your medicine properly.

Store it in a cool dry place away from moisture, heat or sunlight; for example, do not store it:

  • in the bathroom or near a sink, or
  • in the car or on window sills.

Keep it where young children cannot reach it.

Getting rid of any unwanted medicine

If you no longer need to use this medicine or it is out of date, take it to any pharmacy for safe disposal.

Do not use this medicine after the expiry date.

6. Are there any side effects?

All medicines can have side effects. If you do experience any side effects, most of them are minor and temporary. However, some side effects may need medical attention.

See the information below and, if you need to, ask your doctor or pharmacist if you have any further questions about side effects.

Less serious side effects

Less serious side effectsWhat to do
Neurological or brain related:
  • Headache
  • Dizziness
  • Nausea
  • Tiredness
  • Disturbed sleep
Speak to your doctor if you have any of these less serious side effects and they worry you.

Serious side effects

Serious side effectsWhat to do
Gastrointestinal
  • Poor appetite
  • Vomiting
  • Diarrhoea
  • heartburn
Call your doctor straight away, or go straight to the Emergency Department at your nearest hospital if you notice any of these serious side effects.

Tell your doctor or pharmacist if you notice anything else that may be making you feel unwell.

Other side effects not listed here may occur in some people.

Reporting side effects

After you have received medical advice for any side effects you experience, you can report side effects to the Therapeutic Goods Administration online at www.tga.gov.au/reporting-problems. By reporting side effects, you can help provide more information on the safety of this medicine.

Always make sure you speak to your doctor or pharmacist before you decide to stop taking any of your medicines.

7. Product details

This medicine is only available with a doctor's prescription.

What APO-ISOSORBIDE MONONITRATE contains

Active ingredient
(main ingredient)
Isosorbide mononitrate 60 mg
Other ingredients
(inactive ingredients)
stearic acid,
carnauba wax,
hypromellose,
lactose monohydrate,
magnesium stearate,
purified talc,
titanium dioxide,
colloidal anhydrous silica,
macrogol 4000,
iron oxide yellow.
Potential allergensLactose monohydrate

Do not take this medicine if you are allergic to any of these ingredients.

What APO-ISOSORBIDE MONONITRATE looks like

APO-ISOSORBIDE MONONITRATE are oval tablets with a cream coloured film coating and half scored on both sides.

APO-ISOSORBIDE MONONITRATE is available in blisters (AUST R 75240) packs of 30 tablets.

Who distributes APO-ISOSORBIDE MONONITRATE

Arrotex Pharmaceuticals Pty Ltd
15-17 Chapel St
Cremorne 3121 VIC
Australia
www.arrotex.com.au

This leaflet was prepared in January 2024.

Published by MIMS March 2024

BRAND INFORMATION

Brand name

APO-Isosorbide Mononitrate

Active ingredient

Isosorbide mononitrate

Schedule

S4

 

1 Name of Medicine

Isosorbide mononitrate.

2 Qualitative and Quantitative Composition

APO-Isosorbide Mononitrate sustained release tablets contain 60 mg isosorbide mononitrate.

Excipients with known effect.

Lactose monohydrate.
For the full list of excipients see Section 6.1 List of Excipients.

3 Pharmaceutical Form

APO-Isosorbide Mononitrate 60 mg sustained release tablets.

A cream, film-coated oval tablet of 13 mm length, half scored on both sides.

4 Clinical Particulars

4.1 Therapeutic Indications

Prophylactic treatment of angina pectoris. APO-Isosorbide Mononitrate 60 mg sustained release tablets are not recommended for the management of acute attacks of angina pectoris (see Section 4.4 Special Warnings and Precautions for Use).

4.2 Dose and Method of Administration

Dosage.

One (1) tablet once daily. That dose may be increased to two (2) tablets daily, both tablets taken at the same time.
APO-Isosorbide Mononitrate 60 mg sustained release tablets should not be administered twice daily.
There is insufficient evidence to show that one halved tablet of APO-Isosorbide Mononitrate delivers exactly half the dose of one full tablet, or whether the rate of release is the same. In vitro dissolution testing showed that dissolution was slightly faster with halved APO-Isosorbide Mononitrate sustained release tablets than with whole tablets.
APO-Isosorbide Mononitrate 60 mg sustained release tablets should not be chewed or crushed, and should be swallowed whole with half a glass of fluid.

4.3 Contraindications

Known hypersensitivity to nitrates or to any of the components in APO-Isosorbide Mononitrate 60 mg sustained release tablets.
Shock (including cardiogenic shock), hypotension, obstructive hypertrophic cardiomyopathy and pericarditis, aortic stenosis, cardiac tamponade, mitral stenosis and severe anaemia.
Phosphodiesterase type 5 inhibitors (e.g. sildenafil, tadalafil and vardenafil) are contraindicated and must not be given to patients already receiving isosorbide mononitrate therapy.
Concomitant administration of isosorbide mononitrate and phosphodiesterase type 5 inhibitors can potentiate the vasodilatory effect of isosorbide mononitrate with the potential result of serious side effects such as syncope or myocardial infarction.
Severe cerebrovascular insufficiency or hypotension are relative contraindications to the use of isosorbide mononitrate 60 mg sustained release tablets.

Acute angina.

Isosorbide mononitrate 60 mg sustained release tablets are not indicated for the relief of acute attacks of angina; in the event of an acute attack, sublingual or buccal glyceryl trinitrate tablets should be used.

4.4 Special Warnings and Precautions for Use

Note.

There is a risk of developing tolerance to haemodynamic and antianginal effects if higher doses (more than 120 mg/day) and/or more frequent doses (e.g. twice daily) of isosorbide mononitrate 60 mg sustained release tablets are administered. It is, therefore, important that isosorbide mononitrate 60 mg sustained release tablets are administered once a day in order to ensure that intervals with low nitrate concentrations are achieved each day, reducing the risk of the development of tolerance.

Cerebral arteriosclerosis or mitral stenosis.

Caution should be observed if isosorbide mononitrate is administered to patients with severe cerebral arteriosclerosis or pronounced mitral stenosis.

Acute myocardial infarction and congestive cardiac failure.

The benefits of isosorbide mononitrate in patients with acute myocardial infarction or congestive cardiac failure have not been established. Because the effects of isosorbide mononitrate are difficult to terminate rapidly, the medicine is not recommended in these settings. If isosorbide mononitrate is used in these conditions, careful clinical and haemodynamic monitoring is necessary to avoid the hazards of hypotension and tachycardia.

Hypotension.

Severe hypotension, particularly with upright posture, may occur with even small doses of isosorbide mononitrate. Hypotension and lightheadedness on standing may be more frequent in patients who have consumed alcohol. The drug should be used with caution in patients who may be volume depleted or who, for whatever reason, are already hypotensive. Hypotension induced by isosorbide mononitrate may be accompanied by paradoxical bradycardia and increased angina pectoris.

Industrial workers.

Tolerance develops in industrial workers who have had long-term exposure to high doses of organic nitrates. Chest pain, acute myocardial infarction and even sudden death have occurred during temporary withdrawal of nitrates from these workers, demonstrating the existence of true physical dependence.

Check the following before use.

Caution should be observed if isosorbide mononitrate 60 mg sustained release tablets are administered to patients with severe cerebral arteriosclerosis, pronounced mitral stenosis, hypertrophic cardiomyopathy, hypotension or cardiogenic shock.

Use with caution in the following circumstances.

Use in renal impairment.

The elimination of isosorbide mononitrate following administration of an immediate release tablet, but not a sustained release tablet, has been investigated in patients with severe renal impairment, but not using the sustained release tablet. Renal impairment makes no therapeutically important difference to the pharmacokinetics of isosorbide mononitrate administered as an immediate release tablet, although two single dose studies did indicate a prolonged half-life in these patients with severe renal impairment. One of these studies also showed a higher plasma concentration. In view of the lack of data regarding the use of the tablet presentation in patients with severe renal impairment, the possibility of accumulation should be borne in mind when administering isosorbide mononitrate 60 mg sustained release tablets to such patients, in whom a reduced dosage may be appropriate.

Use in hepatic impairment.

Isosorbide mononitrate has been shown to cause a significant decrease in portal pressure in patients with cirrhosis and portal hypertension during long-term therapy (see Section 4.5 Interactions with Other Medicines and Other Forms of Interactions, Propranolol).

Abrupt withdrawal.

Although no clear cut rebound phenomena were seen upon abrupt withdrawal of isosorbide mononitrate sustained release tablets, such withdrawal is not recommended because of the possibility of severe exacerbation of anginal symptoms.

Paediatric use.

Due to lack of data, the use of isosorbide mononitrate 60 mg sustained release tablets cannot be recommended in children.

Use in the elderly.

No dose reduction is necessary in elderly patients unless they have severe renal impairment.

Effects on laboratory tests.

No data available.

4.5 Interactions with Other Medicines and Other Forms of Interactions

Phosphodiesterase type 5 inhibitors.

Concomitant administration of isosorbide mononitrate and phosphodiesterase type 5 inhibitors can potentiate the vasodilatory effect of isosorbide mononitrate with the potential result of serious side effects such as syncope or myocardial infarction. Therefore, phosphodiesterase type 5 inhibitors (e.g. sildenafil, tadalafil and vardenafil) must not be given to patients already receiving isosorbide mononitrate therapy.

Sulfhydryl containing compounds.

The metabolism of organic nitrates to nitric oxide is dependent on the presence of sulfhydryl groups in the muscle. The combination of oral N-acetylcysteine and a single dose of sustained release isosorbide mononitrate 60 mg significantly prolonged the total exercise time in patients with angina pectoris and angiographically proven significant coronary artery disease, when compared with isosorbide mononitrate alone. Concomitant administration of other exogenous sources of sulfhydryl groups such as methionine and captopril may produce a similar interaction.

Phenylalkylamine calcium antagonists.

The addition of a calcium channel blocker of the verapamil type, such as gallopamil 75 mg, has been shown to further improve left ventricular functional parameters when given in combination with isosorbide mononitrate in a sustained release formulation.

Propranolol.

The addition of isosorbide mononitrate to propranolol treatment in patients with cirrhosis and portal hypertension caused a marked fall in portal pressure, a reduction in hepatic blood flow, cardiac output and mean arterial blood pressure, but no additional change in azygos blood flow. The additional effect of isosorbide mononitrate was especially evident in patients whose portal pressure was not reduced by propranolol.

Calcium antagonists (general).

Marked symptomatic orthostatic hypotension has been reported when calcium antagonists and organic nitrates were used in combination. Dose adjustments of either class of agent may be necessary.

4.6 Fertility, Pregnancy and Lactation

Effects on fertility.

No data available.
(Category B2)
The safety of isosorbide mononitrate in pregnancy has not been established. In the absence of segment I and III studies with isosorbide mononitrate, the drug should only be administered to pregnant women if, in the opinion of the physician, the clinical benefits outweigh the potential risks.
At present there is no documentation about the passage of isosorbide mononitrate into breast milk, therefore its use in women who are breastfeeding is not recommended.

4.7 Effects on Ability to Drive and Use Machines

Patients may develop dizziness when first using isosorbide mononitrate. Patients should be advised to determine how they react before they drive or operate machinery.

4.8 Adverse Effects (Undesirable Effects)

Adverse effects associated with the vascular activity of the drug are common and as expected with all nitrate preparations. They occur mainly in the early stages of treatment. Headache predominates (up to 30%), but the incidence reduces rapidly as treatment continues. Only 2-3% of patients withdrew during clinical trials due to this adverse effect.
Hypotension (4%) with symptoms such as dizziness and nausea have been reported. These symptoms generally disappear during long-term treatment.
The adverse reactions which follow have been reported in studies with isosorbide mononitrate.

Very common.

Headache (up to 30%) necessitating withdrawal of 2-3% of patients.

Common.

Tiredness, sleep disturbances (6%) and gastrointestinal disturbances (6%) have been reported during clinical trials with isosorbide mononitrate modified release tablets, but at a frequency no greater than for placebo. Hypotension (4 to 5%), poor appetite (2.5%), nausea (1%).
Adverse effects associated with the clinical use of the drug are as expected with all nitrate preparations. They occur mainly in the early stages of treatment.

Very common.

Headache predominates (up to 30%), but the incidence reduces rapidly as treatment continues.

Common.

Hypotension (4%) with symptoms such as dizziness and nausea have been reported. These symptoms generally disappear during long-term treatment.
Other reactions that have been reported with isosorbide mononitrate modified release tablets include tachycardia, vomiting, diarrhoea, vertigo, fainting, poor appetite, nausea, heartburn, rash and pruritus.
The following adverse events have been observed in the postmarketing period (definitions of frequency: common 1-9.9%; uncommon 0.1-0.9%; rare 0.01-0.09%; very rare < 0.01%).

Central nervous system.

Common: dizziness.

Musculoskeletal.

Very rare: myalgia.

Reporting suspected adverse effects.

Reporting suspected adverse reactions after registration of the medicinal product is important. It allows continued monitoring of the benefit-risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions at http://www.tga.gov.au/reporting-problems and contact Apotex Medical Information Enquiries/Adverse Drug Reaction Reporting on 1800 195 055.

4.9 Overdose

Symptoms.

The most common symptom of overdose is a pulsing headache. More serious symptoms are excitation, flushing, cold sweats, nausea, vomiting, vertigo, syncope, tachycardia and a fall in blood pressure.

Treatment.

Activated charcoal may reduce absorption of the drug if given within one or two hours after ingestion. In patients who are not fully conscious or have impaired gag reflex, consideration should be given to administering activated charcoal via a nasogastric tube, once the airway is protected. In patients with severe hypotension, place patient in supine position with the legs raised. If necessary, further symptomatic treatment should be given, including intravenous fluid administration.
For information on the management of overdose, contact the Poisons Information Centre on 131126 (Australia).

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Mechanism of action.

Isosorbide mononitrate is an active metabolite of isosorbide dinitrate and exerts qualitatively similar effects. Isosorbide mononitrate reduces the workload of the heart by producing venous and arterial dilatation. By reducing the end diastolic pressure and volume, isosorbide mononitrate lowers intramural pressure, hence leading to an improvement in the subendocardial blood flow. The net effect when administering isosorbide mononitrate is, therefore, a reduced workload for the heart and an improvement in the oxygen supply/ demand balance of myocardium.
Nitrates are highly effective in the prophylaxis of symptomatic and asymptomatic myocardial ischaemia. Nitrates dilate coronary arteries not only in pre- and post-stenotic vessels, but also in eccentric lesions. The natural initiator of vascular relaxation is thought to be endothelium derived relaxing factor (EDRF), which has both the clinical and biological characteristics of nitric oxide. Organic nitrates are metabolised to nitric oxide in the muscle cell via a sulfhydryl dependent mechanism. They are, therefore, thought to be the physiological substitute for EDRF.

Clinical trials.

No data available.

5.2 Pharmacokinetic Properties

Isosorbide mononitrate has an elimination half-life of around 5 hours. Isosorbide Mononitrate 60 mg Sustained Release Tablets provide a sustained release presentation of isosorbide mononitrate, with approximately 85% bioavailability. The release mechanism in APO-Isosorbide Mononitrate comprises active drug distributed within a hydrophobic cellulose matrix with release occurring by diffusion. Drug particles close to the tablet surface are released relatively rapidly, but those incorporated more deeply are released more slowly. Administration of isosorbide mononitrate 60 mg sustained release tablets results in a gradual, non-pH dependent release of the active substance, which is completed after approximately 10 hours. Compared to ordinary tablets, the absorption phase is prolonged and the duration of effect is extended. The absorption of isosorbide mononitrate 60 mg sustained release tablets has been shown not to be influenced by food intake.
After repeated once daily administration of isosorbide mononitrate 60 mg sustained release tablets, the maximum plasma level (about 3000 nanomol/L) of isosorbide mononitrate is achieved at about 4 hours. The plasma concentration remains above 1400 to 1500 nanomol/L for approximately 10 hours, dropping to under 500 nanomol/L by the end of the dosage interval (24 hours after dose). This nitrate low period minimises the possibility of nitrate tolerances developing during prolonged treatment with isosorbide mononitrate 60 mg sustained release tablets.
Isosorbide mononitrate is less than 5% plasma protein bound. The distribution volume of isosorbide mononitrate is about 0.6 L/kg, indicating that it is mainly distributed into total body water. Elimination takes place predominantly by hydrolysis of the nitrate and conjugation in the liver. The metabolites are excreted mainly via the kidneys, with only about 2% of the dose being excreted intact.
In placebo controlled studies, isosorbide mononitrate sustained release tablets have been shown to significantly increase exercise capacity in patients with angina pectoris taking no other chronic treatment, as well as in patients taking concomitant β-blocker therapy.
It is known that the clinical effects may be attenuated during repeated administration with nitrates in high doses and/or frequent administration. However, the pharmacokinetic characteristics of isosorbide mononitrate 60 mg sustained release tablets produce a nitrate low period following once daily dosage. No development of tolerance with respect to antianginal effect has been detected when isosorbide mononitrate sustained release tablets are given at a dose of one or two tablets (60 or 120 mg) once daily. The drug is not recommended for twice daily administration.
There is insufficient evidence to show that one halved tablet of APO-Isosorbide Mononitrate delivers exactly half the dose of one full tablet, or whether the rate of release is the same. In vitro dissolution testing showed that dissolution was slightly faster with halved isosorbide mononitrate sustained release tablets than with whole tablets.

5.3 Preclinical Safety Data

Genotoxicity.

No data available.

Carcinogenicity.

No data available.

6 Pharmaceutical Particulars

6.1 List of Excipients

Hypromellose, carnauba wax, stearic acid, lactose monohydrate, colloidal anhydrous silica, magnesium stearate, purified talc, titanium dioxide, iron oxide yellow C177492, macrogol 4000.

6.2 Incompatibilities

Incompatibilities were either not assessed or not identified as part of the registration of this medicine.

6.3 Shelf Life

In Australia, information on the shelf life can be found on the public summary of the Australian Register of Therapeutic Goods (ARTG). The expiry date can be found on the packaging.

6.4 Special Precautions for Storage

Store below 25 degrees. Protect from moisture. Protect from light.

6.5 Nature and Contents of Container

APO-Isosorbide Mononitrate 60 mg sustained release tablets.

30's. AUST R 75240.

6.6 Special Precautions for Disposal

In Australia, any unused medicine or waste material should be disposed of by taking to your local pharmacy.

6.7 Physicochemical Properties

Isosorbide mononitrate is a white to pale yellow, crystalline, odourless powder that is freely soluble in water.

Chemical structure.


Chemical Name: 1,4:3,6-dianhydro-D-glucitol 5-nitrate.
Molecular Formula: C6H9NO6.
Molecular Weight: 191.14.

CAS number.

16051-77-7.

7 Medicine Schedule (Poisons Standard)

S4 - Prescription Only Medicine.

Summary Table of Changes