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Isosorbide mononitrate, extended release

Isosorbide mononitrate, extended release


Imdur is related to an older drug, isosorbide dinitrate, which has long been prescribed to treat angina. This medicine helps the blood vessels relax, and this puts less pressure on the heart.

Isosorbide mononitrate is also available under two other brand names: Ismo and Monoket. The sustained action of Imdur sets it apart. These medicines are used to prevent angina; they do not act quickly enough to be helpful in treating an acute attack.

Side Effects and Interactions

Imdur may cause headache in many of the people who take it.

The headache is closely linked to the beneficial effects of the drug and can’t easily be avoided in susceptible individuals. It can, however, be successfully treated with either aspirin or acetaminophen.

Other side effects include dizziness, nausea, vomiting, changes in heart rhythm, rash or itching, stomach pain, weakness, and agitation.

A dangerous blood condition called methemoglobinemia occurs very rarely. Report any symptoms to the physician promptly.

Imdur may interact with certain other drugs. The manufacturer recommends avoiding alcohol completely and adjusting the dose of calcium channel blockers. Check with your doctor and pharmacist to make sure Imdur is safe in combination with any other drugs you take.

Special Precautions

This medicine is not to be taken during a heart attack or an episode of congestive heart failure. Very low blood pressure, particularly upon sitting or standing up suddenly, may be triggered by isosorbide mononitrate. Patients should use caution when changing position.

Taking the Medicine

Imdur tablets are usually given in the morning right after rising.

They should not be chewed or crushed, although if dosing requires it, they may be broken in half. Swallow with half a glass of liquid.

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
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