Monomak 20 mg

Trade Name:

Monomak 20 mg

Composition

Isosorbide mononitrate 20 mg

Lactose 80 mg

Properties

Isosorbide mononitrate is a direct smooth muscle relaxant which has a prominent action vascular smooth muscles preferentially veins than arteries. It is enzymatically generated in the smooth muscle cells to release the reactive free radical nitric oxide which activates cytosolic guanylyl cyclase thus increases cyclic GMP levels which causes dephosphorylation of myosin light chain kinase(MLCK) through a cyclic GMP dependent protein kinase. Reduced availability of phosphorylated (active) MLCK interferes with activation of myosin and myosin fails to interact with actin to cause contraction and consequently relaxation occurs. Elevated levels of cyclic GMP also reduce calcium entry which also contributes to relaxation. It dilates veins more than arteries because veins have greater amounts of enzymes that generate nitric oxide from nitrates.

Indications

Prophylactic treatment of angina pectoris.

Dosage and administration

Adults: The usual dose of Monomak is 1 tablet of Monomak 20 mg, taken asymmetrically (to allow a nitrate low period) 2 to 3 times daily. If the result is not adequate, the dose may be increased to 1 tablet of Monomak 40 mg taken asymmetrically (to allow a nitrate low period) 2 to 3 times daily. The dosage may be increased to 120 mg per day. Dosage regime should be designed according to the clinical response of the patient. The lowest effective dose should be used. In patients taking Monomak twice daily, the second dose should be taken 8 hours after the 1st dosage. If the dose is one three times daily, take one every 6 hours. This provides a nitrate-free period of 6 — 8 hours. The maximum dose is 3 tablets of Monomak 40 mg per day. In order to prevent possible initial undesirable effects, it may be adequate to initiate treatment with the possible lowest dose and slowly increase to the required dose. To prevent tolerance, it is recommended that the dosage be kept as low as possible and that a sufficiently long nitrate-free interval is ensured to restore sensitivity (first dose in the morning and last dose late in the afternoon, e.g. at 8 am and 3 pm). The duration of application is decided by the treating physician. Treatment with Monomak, as with any other nitrate, should not be stopped suddenly. Both the dosage and frequency should be tapered gradually.

Elderly: There is no evidence to suggest that an adjustment of the dosage is necessary in elderly.

Pediatric: There is no data on the safety and efficacy of Monomak in children.

Contraindications

Hypersensitivity to isosorbide mononitrate or to any of the excipients . Monomak should not be used in cases of acute myocardial infarction with low filling pressure, acute circulatory failure (shock, vascular collapse), or hypertrophic obstructive cardiomyopathy (HOCM), constrictive pericarditis, low cardiac filling pressures, aortic/mitral valve stenosis and diseases associated with a raised intracranial pressure e.g. following a head trauma and including cerebral haemorrhage. Monomak should not be used in patients with severe anaemia, severe hypotension, closed angle glaucoma or severe hypovolaemia. Phosphodiesterase type-5 inhibitors (e.g. sildenafil, tadalafil and vardenafil) have been shown to potentiate the hypotensive effects of nitrates, and their co-administration with nitrates or nitric oxide donors is therefore contraindicated.

Side effects

Abnormal heart beat, absence of or decrease in body movement

arm, back, or jaw pain, black, tarry stools

bladder pain, bleeding after defecation

Storage

Store at a temperature not exceeding 30°C.

Package:

Carton box holds 2 strips of 10 film coated tablets.