- isosorbide mononitrate
This information is intended for use by health professionals
NYZAMAC SR 60MG CAPSULES
Each modified-release capsule contains 60mg of isosorbide mononitrate.
For the full list of excipients, see section 6.1.
Each size 1 capsule contains off-white to yellowish microgranules. The capsule shell has an opaque, white cap and body. "ISMN SR" is axially printed on the cap and "60" is axially printed on the body in black ink.
For the prophylactic treatment of angina pectoris.
Method of administration
For oral use
Capsules may be taken with or without food, and should be swallowed whole and not chewed.
Adults: One capsule to be taken in the morning. This may be increased 120mg if required. The product must not be given in divided doses, as a daily nitrate free period is required in order to prevent the development of tolerance.
Paediatric population: Safety and efficacy in children have not been established.
Older people: There is no evidence of a need for routine dosage adjustment in older people, but special care may be needed in those with increased susceptibility to hypotension or marked hepatic or renal insufficiency.
Hypersensitivity to the active substance or to any of the excipients listed in section 6.1.
This product should not be given to patients with a known sensitivity to nitrates.
Relative contraindications to the use of isosorbide mononitrate are severe cerebral vascular insufficiency and hypotension.
Sildenafil has been shown to potentiate the hypotensive effects of nitrates, and its co-administration with nitrates or nitric oxide donors is therefore contra-indicated.
This product is contraindicated in patients with constrictive pericarditis, pericardial tamponade, restrictive cardiomyopathy and marked anaemia
Isosorbide mononitrate SR 60 mg capsules are not indicated for relief of acute angina attacks; in the event of an acute attack, sublingual or buccal glyceryl trinitrate tablets / sprays should be used.
Isosorbide mononitrate should be used with caution in patients who are predisposed to closed angle glaucoma.
Isosorbide mononitrate should be used with caution in patients suffering from head trauma, cerebral haemorrhage, hypothyroidism, hypothermia, malnutrition, severe liver or renal disease.
Isosorbide mononitrate may give rise to symptoms of postural hypotension and syncope, particularly following the first dose and at higher doses.
Isosorbide mononitrate should be used with caution in patients with aortic or mitral stenosis. It is not suitable for treating angina associated with hypertrophic cardiomyopathy.
Patients with rare hereditary problems of fructose or galactose intolerance, the Lapp lactase deficiency, glucose-galactose malabsorption or sucrase- isomaltase insufficiency should not take this medicine.
Only limited information is available on the possible interaction between isosorbide mononitrate and other drugs.
Vasodilators (including neuroleptics and tricyclic antidepressants), antihypertensives and diuretics may potentiate the hypotension caused by nitrates particularly in older people.
The hypotensive effects of nitrates are potentiated by concurrent administration of sildenafil.
Nyzamac SR Capsules should not be taken at the same time as alcohol. In vitro data suggests that in combination with Nyzamac SR Capsules, alcohol may increase the rate of in vivo release of the product from the prolonged release preparation. Alcohol may increase dose-dependent effects and lead to potential adverse pharmacodynamic interactions. Alcohol use could therefore increase the rate and seriousness of isosorbide 5-mononitrate adverse drug reactions such as vasodilatory related events.
There is no evidence of interaction with food.
There is inadequate evidence of safety of the drug in human pregnancy, although animal studies have shown no evidence of teratogenicity. This product should therefore not be used during pregnancy or lactation unless considered essential by the physician.
Since postural hypotension with symptoms such as dizziness has been reported, patients should be advised to be careful when driving or operating machinery if they suffer from these symptoms.
Most of the adverse reactions are pharmacodynamically mediated and dose dependent. Side effects including flushing, postural hypotension, pruritis and dry skin rashes may occur occasionally. Headache may occur at the onset of treatment but may be minimised by commencing with low doses of 30mg and gradually increasing the dose. Hypotension, with symptoms such as dizziness and nausea, has occasionally been reported.
Using the recommended dosage schedules there is no evidence of development of nitrate tolerance.
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation 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 via the Yellow Card Scheme at www.mhra.gov.uk/yellowcard.
A pulsating headache is the commonest.
More serious symptoms are excitation, flushing, cold perspiration, nausea, vomiting, vertigo, syncope, tachycardia and a fall in blood pressure.
Induce emesis. Use activated charcoal.
Treatment should be symptomatic with appropriate measures to support the circulation. The main symptom is likely to be hypotension.
If pronounced hypotension, place the patient in the supine position with legs raised. If necessary, intravenous fluids should be administered.
The principal pharmacological action of isosorbide mononitrate, an active metabolite of isosorbide dinitrate, is relaxation of vascular smooth muscle, producing vasodilation of both arteries and veins with the venous effect predominating. The effect of the treatment is dependent on the dose. Low plasma concentrations lead to venous dilation, resulting in peripheral pooling of blood, decreased venous return and reduction in left ventricular end-diastolic pressure (preload). High plasma concentration also dilates the arteries, reducing systemic vascular resistance and arterial pressure and thus a reduction in cardiac after-load. Isosorbide mononitrate may also dilate the coronary arteries directly. By reducing the end-diastolic pressure and volume, the preparation lowers the intramural pressure, this in turn leading to an improvement in subendocardial blood flow.
The net effect, when administering isosorbide mononitrate, is therefore a reduced workload on the heart and an improved oxygen supply/demand balance in the myocardium.
In man, isosorbide mononitrate is absorbed completely and rapidly following oral administration.
Isosorbide mononitrate is not subject to the "hepatic first-pass" effect, and provides a low degree of inter-individual variation of blood levels, leading to predictable and reproducible clinical effects.
Isosorbide mononitrate SR 60mg capsules have all the pharmacokinetic characteristics of a true modified-release dosage form. Compared with an immediate-release dosage form, the peak plasma concentration obtained is lower and occurs later, while the apparent elimination half-life is unchanged. Thus compared to ordinary capsules, the absorption phase is prolonged and the duration of effect is extended.
Isosorbide mononitrate is effective in monotherapy as well as in combination with long term ß-blocker therapy.
The clinical effects of nitrates may be reduced following repeated administration due to too high and/or constant plasma levels. This can be avoided by allowing low plasma levels for a certain period between doses.
The slow continuous diffusion of the active ingredient from the modified-release microgranules makes it possible, at steady state, to maintain plasma concentrations above the putative effective level of 100ng/ml for a period of about 16 hours for the 40mg capsules and 20 hours for the 60mg capsules.
Thus, no development of tolerance should be seen with isosorbide mononitrate SR capsules when they are taken in accordance with the recommended dosage regime.
Isosorbide mononitrate produces very few toxic effects and is less toxic than isosorbide dinitrate. After chronic administration at high doses (60mg/kg), signs of toxicity have been detected in canine liver and kidneys. Tests conducted have shown no evidence of a teratogenic or mutagenic potential.
For Microgranule Coating:
Bleached dewaxed shellac,
Copolymer of methacrylic acid and methyl methacrylate (1:1),
Copolymer of ethyl acrylate, methyl methacrylate and
Trimethylammonioethyl methacrylate chloride (1:2:0.1)
For Capsule Shell:
Titanium dioxide (E.171)
Iron oxide (E.172)
Store in the original package. Do not store above 25°C.
The capsules are enclosed in blisters composed of 250μm PVC film/20μm aluminium foil.
The blisters are packed into folded printed cardboard cartons with a patient information leaflet. Packs contain 8 (sample packs only), 28, 30, 56 or 60 modified-release capsules.
194, Bureaux de la Colline – Bâtiment D
92213 Saint-Cloud Cedex
2nd April 1996; 1st August 2001