Consumer medicine information

Duride

Isosorbide mononitrate

BRAND INFORMATION

Brand name

Duride

Active ingredient

Isosorbide mononitrate

Schedule

S4

 

Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using Duride.

SUMMARY CMI

DURIDE®

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 DURIDE?

DURIDE contains the active ingredient isosorbide mononitrate. DURIDE is used to prevent angina.
For more information, see Section 1. Why am I using DURIDE? in the full CMI.

2. What should I know before I use DURIDE?

Do not use if you have ever had an allergic reaction to DURIDE 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 DURIDE? in the full CMI.

3. What if I am taking other medicines?

Some medicines may interfere with DURIDE 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 DURIDE?

  • Your doctor will decide the right dose for you.
  • The usual dose is one tablet once a day.

More instructions can be found in Section 4. How do I use DURIDE? in the full CMI.

5. What should I know while using DURIDE?

Things you should do
  • Remind any doctor, dentist or pharmacist you visit that you are using DURIDE.
  • If you become pregnant while taking this medicine, tell your doctor immediately.
  • Keep all of your doctor's appointments so that your progress can be checked.
  • If you continue to have angina attacks, or if they become frequent while you are taking DURIDE tell your doctor.
Things you should not do
  • Do not use DURIDE to relieve acute attacks of angina.
  • Do not take DURIDE to treat any other complaints unless your doctor tells you to.
  • Do not stop taking your medicine, or change the dose, without checking with your doctor.
Driving or using machines
  • Be careful driving or operating machinery until you know how DURIDE affects you.
Drinking alcohol
  • Be careful when drinking alcohol while taking DURIDE.
  • Combining DURIDE and alcohol can make you more sleepy, dizzy or lightheaded, due to a drop in your blood pressure.
Looking after your medicine
  • Keep your tablets in a cool dry place where the temperature stays below 30°C.
  • Do not store DURIDE or any other medicine in the bathroom or near a sink. Do not leave it on a window sill or in the car.
  • Keep your tablets where young children cannot reach it.

For more information, see Section 5. What should I know while using DURIDE? in the full CMI.

6. Are there any side effects?

Tell your doctor or pharmacist if you notice any of the following and they worry you: headache, dizziness, light-headedness or feeling faint, feeling sick (nausea), rapid heart beat, poor appetite, vomiting, heartburn, diarrhoea, rash, itching, muscle tenderness or weakness not caused by exercise, tiredness or sleep disturbances.

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

DURIDE®

Active ingredient(s): isosorbide mononitrate


Consumer Medicine Information (CMI)

This leaflet provides important information about using DURIDE. 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 DURIDE.

Where to find information in this leaflet:

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

1. Why am I using DURIDE?

DURIDE contains the active ingredient isosorbide mononitrate. DURIDE belongs to a group of medicines called nitrates. These medicines work by widening blood vessels, letting more blood and oxygen reach the heart.

DURIDE is used to prevent angina.

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 your heart. The pain of angina is usually brought on by exercise or stress.

Ask your doctor if you have any questions about why this medicine has been prescribed for you.

Your doctor may have prescribed it for another reason.

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

This medicine is not addictive.

There is not enough information to recommend the use of this medicine for children.

2. What should I know before I use DURIDE?

Warnings

Do not use DURIDE if:

  • you are allergic to any medicine containing isosorbide mononitrate or any of the ingredients listed at the end of this leaflet. Some of the symptoms of an allergic reaction may include:
    - shortness of breath
    - wheezing or difficulty breathing
    - swelling of the face, lips, tongue or other parts of the body
    - rash, itching or hives on the skin
    Always check the ingredients to make sure you can use this medicine.
  • you are taking medicines used to treat impotence, including sildenafil (Viagra), tadalafil (Cialis) and vardenafil (Levitra).
  • you have:
    - low blood pressure
    - experienced shock, including it being caused by low blood pressure or heart failure
    - swelling of the lining that surrounds the heart (pericarditis)
    - a weakened heart muscle
  • the expiry date printed on the pack has passed or the packaging is torn or shows signs of tampering.
    If it has expired or is damaged, return it to your pharmacist for disposal.

Do not take DURIDE to relieve acute angina.

This medicine should only be used for the prevention of angina.

Do not give this medicine to children.

Safety and effectiveness in children have not been established.

If you are not sure whether you should start taking this medicine, talk to your doctor.

Check with your doctor if you:

  • have allergies to any other medicines, foods, preservatives or dyes
  • have or have had any of the following medical conditions:
    - liver problems
    - kidney problems
    - low blood pressure (this can make you feel faint, weak or dizzy, especially when you stand up suddenly)
    - heart or blood vessel disease
  • are or have been an industrial worker, as you may have had long-term exposure to organic nitrates, which may affect how your body responds to DURIDE.

If you have not told your doctor about any of the above, tell them before you start taking DURIDE.

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 this medicine if you are pregnant.

It may affect your developing baby if taken during pregnancy.

Do not breast-feed if you are taking this medicine unless your doctor says it is safe.

It is not known whether DURIDE is passed into breast milk, therefore it is not recommended if you are breastfeeding.

Tell your doctor if you are pregnant or plan to become pregnant or are breast-feeding.

Your doctor can discuss with you the risks and benefits involved.

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 and DURIDE may be interfere with each other. These include:

  • medicines used to treat high blood pressure and heart conditions, such as calcium antagonists
  • medicines used to treat liver disease, such as propranolol
  • medicines used to treat impotence in men, such as sildenafil (Viagra), tadalafil (Cialis) and vardenafil (Levitra)

These medicines may be affected by DURIDE or may affect how well it works. You may need different amounts of your medicines, or you may need to take different medicines.

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

4. How do I use DURIDE?

Follow all directions given to you by your doctor and pharmacist carefully.

They may differ from the information contained in this leaflet.

If you do not understand the instructions on the box, ask your doctor or pharmacist for help.

How much to take

  • The usual dose is one tablet once a day.
  • Some patients may need a different dose.
  • Your doctor will decide the right dose for you.

How to take it

  • Swallow the tablets whole with half a glass of water.
    DURIDE tablets can be broken in half if care is taken not to crumble them. Break the tablet in half with care if your doctor has prescribed half a tablet.
  • Do not crush or chew the tablets.
    DURIDE tablets are modified release tablets. This means that the medicine is released into the blood over an extended period of time. If you crush or chew the tablets, they will not work as well.

When to take it

  • Take your medicine at about the same time each day.
    Taking it at the same time each day will have the best effect. It will also help you remember when to take it.
  • It does not matter if you take this medicine before or after food.
  • If your doctor tells you to take two tablets each day, take both tablets at the same time.

How long to take it for

Continue taking your medicine for as long as your doctor tells you.

This medicine helps to control your angina but does not cure it. It is important to keep taking your medicine even if you feel well.

If you forget to take DURIDE

If it is more than 8 hours since you should have taken your dose, skip the dose you missed and take your next dose when you are meant to.

Otherwise, take it as soon as you remember, and then go back to taking your medicine as you would normally.

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

If you miss a dose of DURIDE, you may get attacks of angina.

If you are not sure what to do, ask your doctor or pharmacist.

If you have trouble remembering to take your medicine, ask your pharmacist for some hints.

If you use too much DURIDE

If you think that you have used too much DURIDE, you may need urgent medical attention.

You should immediately:

  • phone the Poisons Information Centre
    (Australia telephone 13 11 26) for advice, 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.

You may need urgent medical attention.

If you take too much DURIDE, you may experience a headache, a fast heart beat and feel dizzy or faint. You may feel excited, flushed, have cold sweats, feel sick or vomit.

5. What should I know while using DURIDE?

Things you should do

  • If you are about to be started on any new medicine, remind your doctor and pharmacist that you are taking DURIDE.
  • Tell any other doctors, dentists and pharmacists who treat you that you are taking this medicine.
  • If you become pregnant while taking this medicine, tell your doctor immediately.
  • Keep all of your doctor's appointments so that your progress can be checked.
  • If you continue to have angina attacks, or if they become frequent while you are taking DURIDE tell your doctor.

Things you should not do

  • Do not use DURIDE to relieve acute attacks of angina.
    This medicine is used to prevent angina. Your doctor will have given you other medicines to use if you have an angina attack.
  • Do not take DURIDE to treat any other complaints unless your doctor tells you to.
  • Do not give your medicine to anyone else, even if they have the same condition as you.
  • Do not stop taking your medicine, or change the dose, without checking with your doctor.
    If you stop taking it suddenly, your angina may worsen, or you may have unwanted side effects.

Things to be careful of

You will probably feel better when you start to take DURIDE but be careful not to overdo physical activities straight away.

You will need time to improve your physical fitness.

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

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

Driving or using machines

Be careful before you drive or use any machines or tools until you know how DURIDE affects you.

This medicine may cause dizziness, light-headedness or fainting in some people. If any have any of these symptoms, do not drive, operate machinery or do anything that could be dangerous.

Drinking alcohol

Be careful when drinking alcohol while taking DURIDE.

Combining DURIDE and alcohol can make you more sleepy, dizzy or lightheaded, due to a drop in your blood pressure.

After using DURIDE

Be aware that the outer shell of the DURIDE tablet passes through the body. This does not affect the way it works.

DURIDE tablets are made of a wax-like shell which does not dissolve in the body. After the active ingredient, isosorbide mononitrate, has been absorbed into the body, you may see this empty tablet shell in your faeces (bowel motions).

Looking after your medicine

Keep your tablets in the pack until it is time to take them.

If you take the tablets out of the pack they may not keep well.

Keep your tablets in a cool dry place where the temperature stays below 30°C.

Do not store DURIDE or any other medicine in the bathroom or near a sink. Do not leave it on a window sill or in the car.

Heat and dampness can destroy some medicines.

Keep it where young children cannot reach it.

A locked cupboard at least one-and-a-half metres above the ground is a good place to store medicines.

Getting rid of any unwanted medicine

If your doctor tells you to stop taking this medicine, or the expiry date has passed, ask your pharmacist what to do with any medicine that is left over.

6. Are there any side effects?

Tell your doctor or pharmacist as soon as possible if you do not feel well while you are taking DURIDE.

This medicine helps most people with angina, but it may have unwanted side effects in some people. 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.

Do not be alarmed by the following lists of side effects. You may not experience any of them.

Side effects

Side effectsWhat to do
  • headache
  • dizziness, light-headedness or feeling faint
  • feeling sick (nausea)
  • rapid heart beat
  • poor appetite
  • vomiting
  • heartburn
  • diarrhoea
  • rash, itching
  • muscle tenderness or weakness not caused by exercise
  • tiredness or sleep disturbances
Tell your doctor or pharmacist if you notice any of the following and they worry you:

Tell your doctor or pharmacist if you notice anything that is making you feel unwell.

Other side effects not listed above may also 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 DURIDE contains

Active ingredient
(main ingredient)
isosorbide mononitrate 60 mg
Other ingredients
(inactive ingredients)
aluminium silicate
colloidal anhydrous silica
magnesium stearate
microcrystalline cellulose
Opadry Yellow OY-LS-22814 (ARTG PI No: 2828)
Paraflint Med 851 (ARTG PI No: 2858)
Potential allergensDURIDE contains lactose and sulfites.

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

What DURIDE looks like

DURIDE is a yellow, film coated, elliptical shaped tablet, 13.1 x 7.1 mm, scored on both sides and imprinted "IM I 60" on one side. Each pack contains 30 tablets. (AUST R 60907).

Who distributes DURIDE

Alphapharm Pty Ltd trading as Viatris
Level 1, 30 The Bond
30-34 Hickson Road
Millers Point NSW 2000
www.viatris.com.au
Phone: 1800 274 276

This leaflet was prepared in July 2022.

DURIDE_cmi\Jul22/00

Published by MIMS September 2022

BRAND INFORMATION

Brand name

Duride

Active ingredient

Isosorbide mononitrate

Schedule

S4

 

1 Name of Medicine

Isosorbide mononitrate.

2 Qualitative and Quantitative Composition

Each modified-release tablet contains 60 mg of isosorbide mononitrate as the active ingredient.

Excipients of known effect.

Lactose and sulfites.
For the full list of excipients, see Section 6.1 List of Excipients.

3 Pharmaceutical Form

Duride tablets are yellow, film coated, elliptical shaped tablet, 13.1 x 7.1 mm, scored on both sides and imprinted "IM/60" on one side.

4 Clinical Particulars

4.1 Therapeutic Indications

Duride is indicated for the prophylactic treatment of angina pectoris.
Duride is 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

One 60 mg tablet once daily. The dose may be increased to 120 mg once daily. Both tablets should be taken at the same time.
Duride should not be administered twice daily.
If headache occurs, the initial dose may be reduced to half a tablet once a day until the headache disappears. Patients with severe renal impairment may require dosage reduction to half a tablet given once daily.
Duride tablets should be swallowed whole with half a glass of fluid.
The tablets should not be crushed or chewed.
Half tablet doses may be administered without affecting the modified-release properties of Duride, if care is taken not to crush or chew the tablets.

4.3 Contraindications

Known hypersensitivity to nitrates or to any of the ingredients in Duride.
Shock (including cardiogenic shock), hypotension, obstructive hypertrophic cardiomyopathy and pericarditis.
Phosphodiesterase type 5 inhibitors (e.g. sildenafil, tadalafil and vardenafil) must not be given concomitantly with Duride.

4.4 Special Warnings and Precautions for Use

Please 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 Duride are administered. It is important to give Duride modified-release tablets once daily to ensure that intervals with low nitrate concentrations are achieved each day, reducing the risk of tolerance developing.
Caution should also be observed if Duride modified-release tablets are administered to patients with: severe cerebral arteriosclerosis; pronounced mitral stenosis; hypotension.

Acute angina.

Duride is not indicated for the relief of acute attacks of angina.

Abrupt withdrawal.

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

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.

Use in hepatic impairment.

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

Use in renal impairment.

The elimination of isosorbide mononitrate following administration of an immediate-release tablet, but not a modified-release tablet, has been investigated in patients with severe renal impairment. 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 modified-release tablets in patients with severe renal impairment, the possibility of accumulation should be borne in mind. A reduced dosage may be appropriate when Duride is prescribed for such patients.

Use in the elderly.

No dose reduction is necessary in elderly patients unless they have severe renal impairment (see Section 4.4 Special Warnings and Precautions for Use).

Paediatric use.

Due to lack of data, the use of Duride cannot be recommended in children.

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) should 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. In patients with angina pectoris and angio-graphically proven significant coronary artery disease, the combination of oral N-acetylcysteine with a single dose of modified-release isosorbide mononitrate 60 mg prolonged total exercise time significantly, compared with isosorbide mononitrate alone. Other exogenous sources of sulfhydryl groups such as methionine and captopril may produce a similar interaction when administered together with Duride.

Phenylalkylamine calcium antagonists.

Left ventricular functional parameters have been shown to be further improved when a calcium channel blocker of the verapamil type (e.g. gallopamil) is added to therapy with modified-release isosorbide mononitrate tablets.

Propranolol.

Adding isosorbide mononitrate to propranolol treatment in patients with cirrhosis and portal hypertension led to a marked fall in portal pressure, a reduction in hepatic blood flow, cardiac output and mean arterial blood pressure. There were no additional changes in azygos blood flow. In patients whose portal pressure was not reduced by propranolol, the added effect of isosorbide mononitrate was particularly apparent.

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 agents 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 undertaken 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 Duride. 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 isosorbide mononitrate are common and as expected with all nitrate preparations. They occur mainly in the early stages of treatment. Headache predominates (up to 30%). However, the incidence of headache reduces rapidly as treatment continues. Only 2 to 3% of patients withdrew from clinical trials of isosorbide mononitrate 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 following adverse reactions have been reported in studies with isosorbide mononitrate.

Cardiovascular.

Hypotension (4 to 5%), tachycardia.

Central nervous system.

Headache, vertigo, fainting.

Gastrointestinal.

Poor appetite (2.5%), nausea (1%), vomiting, diarrhoea, heartburn.

Skin.

Rash, pruritus.
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.
The following adverse events have been observed in the post-marketing 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 www.tga.gov.au/reporting-problems.

4.9 Overdose

Symptoms.

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

Treatment.

Administer activated charcoal. In patients with severe hypotension, place patient in a supine position with the legs raised. Further symptomatic treatment, including intravenous fluid administration, should be given if necessary.
For information on the management of overdose, contact the Poisons Information Centre on 13 11 26 (Australia).

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Mechanism of action.

Isosorbide mononitrate is an active metabolite of isosorbide dinitrate. It has qualitatively similar effects. Isosorbide mononitrate reduces the workload of the heart by producing venous and arterial dilatation. It lowers intramural pressure by reducing the end diastolic pressure and volume. This leads to an improvement in the subendocardial blood flow. When isosorbide mononitrate is administered, the net effect is therefore a reduced workload for the heart and an improvement in the oxygen supply/ demand balance of the myocardium.
Nitrates are highly effective in the prophylaxis of symptomatic and asymptomatic myocardial ischaemia. Nitrates dilate coronary arteries in pre- and poststenotic vessels and also in eccentric lesions. Vascular relaxation is thought to be initiated naturally by endothelium derived relaxing factor (EDRF). EDRF has both the clinical and biological characteristics of nitric oxide. In muscle cells, organic nitrates are metabolised to nitric oxide via a sulfhydryl dependent mechanism. Organic nitrates are therefore thought to act as a physiological substitute for EDRF.

Clinical trials.

No data available.

5.2 Pharmacokinetic Properties

Absorption.

Administration of isosorbide mononitrate results in a gradual, non-pH dependent release of the active substance, which is completed after approximately 10 hours. The absorption phase is extended and the duration of effect is lengthened when compared to immediate release tablets. The intake of food has been shown not to influence the absorption of isosorbide mononitrate.
In a bioequivalence study comparing Duride sustained release tablets with the Australian brand leader, repeated once daily administration of 60 mg of both brands resulted in maximum plasma levels of isosorbide mononitrate of about 400 nanogram/mL, which were reached at around 3 hours. The plasma concentrations remained above 200 nanogram/mL for approximately 10 hours, dropping to under 100 nanogram/mL by the end of the dosage interval (24 hours after dose) for both brands.
The possibility of nitrate tolerance developing during prolonged treatment with Duride is minimised by the nitrate low period that occurs within each dosing interval.

Distribution.

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 distributed mainly into total body water.

Metabolism.

Isosorbide mononitrate has an elimination half-life of around 5 hours. Duride tablets are a modified-release preparation of isosorbide mononitrate.

Excretion.

Elimination takes place mainly by denitrification and conjugation in the liver. The metabolites are excreted predominantly via the kidneys. Only about 2% of the dose is excreted intact.

Pharmacokinetics in special populations.

In placebo controlled studies, isosorbide mononitrate modified-release tablets have been shown to significantly increase exercise capacity in patients with angina pectoris. This effect was seen both in patients not taking any other chronic treatment and in those taking β-blocker therapy concomitantly.
It is known that the clinical effects of nitrates may be diminished during repeated administration with high and/or frequent doses. However, the pharmacokinetic characteristics of isosorbide mononitrate modified-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 modified-release tablets are given at a dose of 60 mg or 120 mg once daily (one to two tablets). Twice daily dosing with Duride is not recommended.
Pharmacokinetics studies suggest that absorption of isosorbide mononitrate modified-release tablets is slower in some patients with acute myocardial infarction compared to healthy volunteers. At steady state absorption of isosorbide mononitrate is similar in patients with acute myocardial infarction and in healthy volunteers. The steady state elimination half-life is longer in patients with acute myocardial infarction compared to healthy volunteers (see Section 4.4 Special Warnings and Precautions for Use, Acute myocardial infarction and congestive cardiac failure).

5.3 Preclinical Safety Data

Genotoxicity.

No data available.

Carcinogenicity.

No data available.

6 Pharmaceutical Particulars

6.1 List of Excipients

Duride modified-release tablets contain the following inactive ingredients: aluminium silicate, colloidal anhydrous silica, magnesium stearate, microcrystalline cellulose, Opadry Yellow OY-LS-22814 (ARTG PI No: 2828) and Paraflint Med 851 (ARTG PI No: 2858).

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 30°C.

6.5 Nature and Contents of Container

Container type: blister pack.
Pack size: 30.
Some strengths, pack sizes and/or pack types may not be marketed.

Australian register of therapeutic goods (ARTG).

AUST R 60907 - Duride Isosorbide mononitrate 60 mg tablet blister pack.

6.6 Special Precautions for Disposal

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

6.7 Physicochemical Properties

Chemical structure.

Isosorbide mononitrate is a white crystalline powder and is freely soluble in water.
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