What is isosorbide mononitrate, and how does it work (mechanism of action)?

Isosorbide mononitrate is in the
class of drugs called nitrates that are used for treating and preventing
Other nitrates include
(Nitrostat, NitroQuick, Nitrolingual, Nitro-Dur and others) and
dinitrate (Isordil Titradose, Dilatrate-SR, Isochron). Nitrates are
vasodilators (dilators of blood vessels). Blood returning from the body in the
veins must be pumped by the heart through the lungs and into the body’s arteries
against the high pressure in the arteries. In order to accomplish this work, the
heart’s muscle must produce and use energy (“fuel”) which requires oxygen
brought to the heart by the blood. The FDA approved isosorbide mononitrate in
December 1991.

Angina pectoris (angina) or “heart pain” is due to an inadequate flow of
blood (and oxygen) to the muscle of the heart. Nitrates, including isosorbide
mononitrate, correct the imbalance between the flow of blood and oxygen to the
heart and the work that the heart must do by dilating the arteries and veins in
the body. Dilation of the veins reduces the amount of blood that returns to the
heart that must be pumped. Dilation of the arteries lowers the pressure in the
arteries against which the heart must pump. As a consequence of both effects,
the heart works less and requires less blood and oxygen.

What brand names are available for isosorbide mononitrate?

Imdur (discontinued brand), Ismo (discontinued brand), Monoket

Is isosorbide mononitrate available as a generic drug?


Do I need a prescription for isosorbide mononitrate?


What are the side effects of isosorbide mononitrate?

Headaches are the most common side effect of isosorbide mononitrate and usually are dose related (increase with higher doses). Flushing may occur because isosorbide mononitrate dilates (enlarges) blood vessels. Isosorbide mononitrate may cause a severe drop in blood pressure when rising from a sitting position, causing: 

To reduce the risk of low blood pressure, patients should rise slowly from a sitting position.

Medically Reviewed by a Doctor on 5/10/2017

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