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Questions and Answers

Q
I have been given a prescription for 60 milligrams of Imdur and am experiencing dizziness, vertigo and general malaise to the point that I am not sure it is better to take this drug or endure my bouts with Angina. Is is safe to cut my dosage in half and see what happens?
A
... just got a tag on 'Imdur' - it is isosorbide mononitrate, one of several organic nitrate vasodilators. The side-effects you describe are not that uncommon ... light headedness on standing, especially just after rising from a recumbant or seated position is due to the desired vasodilating effect and is additive to vasodilation from other drugs , or very importantly, the ingestion of alcohol.

Just as with all drugs, the proper dose is that which produces a desired, or close to desired, effect and at the same time no, or tolerable, side-effects. From what you say, your starting dose seems to be too high.

The recommended starting dose is 30mg. or 60mg. given once daily. After several days, the dosage may be increased to 120mg. given once daily ... the tablet/s should be taken in the morning on arising.

Hope this helps. Best wishes.