Imdur - Ingredients, uses, doses and precautions for use

Article written by Pharmacist Quang Anh Nguyet - Faculty of Pharmacy - Vinmec Central Park International General Hospital

1.1 Composition Each extended release tablet contains 30mg or 60mg of Isosorbide 5-mononitrate.
1.2 Uses Dilates vascular smooth muscle, leading to varicose veins and arteries, the effects of which are predominant. Vasodilation leads to increased peripheral blood storage, decreased venous return, and decreased left ventricular end-diastolic pressure (preload). High plasma drug concentrations also dilate the arteries, thereby reducing vascular resistance and blood pressure leading to a decrease in afterload.
Therefore, the synergistic effect of isosorbide-5-mononitrate is to reduce the load on the heart and improve the myocardial oxygen supply/demand balance.
1.3 Indications for angina prophylactic treatment

2.1 Dose 60 mg/time/day in the morning. May be increased to 120 mg/day administered once in the morning. To minimize the chance of a headache, the starting dose may be reduced to 30 mg/day for the first 2-4 days.
2.2 How to use, precautions for use Can be taken or not taken with food.
The 30mg and 60mg tablets are slotted and can be broken in half. The whole tablet or half of the tablet should not be chewed or crushed and should be taken with half a glass of water. Imdur is not indicated for the relief of acute angina pectoris, in which case nitroglycerin tablets should be administered sublingually or in the mouth or as aerosol sprays.

Most adverse reactions were pharmacodynamically related and dose dependent. Headache may occur at the beginning of treatment. Hypotension, with symptoms such as dizziness and nausea with syncope, has been reported occasionally. These symptoms usually disappear with continued treatment.

Common (≥ 1/100 to < 1/10)
Hypotension, tachycardia. Headache, dizziness. Nausea Uncommon (≥ 1/1000 to < 1/100)
Vomiting, diarrhea.
Rare (≥ 1/10,000 to < 1/100)
Rash, pruritus.
Very rare (< 1/10,000)
Myalgia.

The safety and effectiveness of Imdur during pregnancy and lactation have not been established. Imdur should not be used by pregnant or nursing women.

5.1 Overdose and management Symptoms
Pulse-type headache. More severe symptoms are irritability, flushing, cold sweats, nausea, vomiting, dizziness, fainting, tachycardia, and low blood pressure.
Treatment
Induce vomiting, use activated charcoal orally. In case of severe hypotension, place the patient in the supine position, with the legs elevated. Intravenous fluids, if needed.
5.2 Contraindications Hypersensitivity to the active substance or to any of the excipients.
Shock, hypotension, hypertrophic obstructive cardiomyopathy and pericarditis, aortic stenosis, severe anemia, right ventricular myocardial infarction. If you are taking Imdur, do not take phosphodiesterase type 5 inhibitors (such as sildenafil, also known under the brand name Viagra).
5.3 Caution Patients with severe cerebral atherosclerosis and hypotension should be carefully monitored. Patients may experience dizziness when using Imdur for the first time. Patients should determine the effects of Imdur on themselves before driving or operating machinery.