Isosorbide mononitrate is a drug used principally in the treatment of angina pectoris.
. and acts by dilating the blood vessels so as to reduce the blood pressure. It is sold by AstraZeneca under the trade name Imdur.
Isosorbide mononitrate is used to for the the prophylactic treatment of angina pectoris; that is, it is taken in order to prevent or at least reduce the occurrence of angina. Research on Isosorbide mononitrate as a cervical ripener to reduce time at hospital to birth is supportive.
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 dilation. 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 the myocardium.
The adverse reactions which follow have been reported in studies with isosorbide mononitrate:
Very common. Headache predominates (up to 30%) necessitating withdrawal of 2 to 3 % of patients, but the incidence reduces rapidly as treatment continues .
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.
Hypotension (4%) with symptoms such as dizziness and nausea (1%) 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 and heartburn