Also indexed as: Imdur, ISMO, Isotrate, Monoket
Isosorbide mononitrate (ISMN) is a member of the nitrate family of drugs used to prevent angina (chest pain). It is available in
immediate-release and extended-release products.
Summary of
Interactions with Vitamins, Herbs, and Foods
In some cases, an herb or supplement may appear in more than one category, which may seem
contradictory. For clarification, read the full article for details about the summarized
interactions.
 May Be Beneficial: Supportive
interaction—Taking these supplements may support or otherwise help your medication
work better. |
N-acetyl cysteine
|
Check: Other—Before taking any of these supplements or eating any of
these foods with your medication, read this article in full for details. |
Vitamin C
|
| Depletion or interference |
None known
|
| Side effect reduction/prevention |
None known
|
| Reduced drug
absorption/bioavailability |
None known
|
| Adverse interaction |
None known
|
An asterisk (*) next to an item in the summary indicates that the
interaction is supported only by weak, fragmentary, and/or contradictory scientific
evidence.
Interactions with Dietary Supplements
N-acetyl cysteine
(NAC)
In a double-blind trial, sustained-release ISMN plus oral NAC (2,400 mg twice per day) for two
days led to significantly longer exercise time than ISMN plus placebo.1 This
outcome suggests that NAC may have increased the efficacy of ISMN. There were no differences
in side effects between the two groups.
Vitamin
C
Some persons taking nitroglycerin or
isosorbide mononitrate may find that it loses efficacy over time. This is because the body
adapts to the drug, a process known as developing tolerance. One study found that taking 2
grams three times daily of vitamin C can decrease this effect when nitroglycerin patches are
simultaneously used.2 Similar benefits have been confirmed in another
study.3 However, it should be noted that it is also possible to avoid tolerance to
these drugs by simply changing the dosing schedule. People taking ISMN or nitroglycerin should
talk with their pharmacists about avoiding drug tolerance.
Interactions with Foods and Other Compounds
Food
Isosorbide mononitrate should be taken on an empty stomach with a glass of water.4
Imdur® may be taken with or without food5 and should be swallowed whole,
without chewing or crushing.6
Alcohol
Isosorbide mononitrate causes low blood pressure. Alcohol may increase this effect, leading to
dangerously low blood pressure and other side effects.7 To prevent problems, people
taking isosorbide mononitrate should avoid alcohol.
References:1. Svendsen JH, Klarlund K, Aldershvile J, Waldorff S. N-acetylcysteine
modifies the acute effects of isosorbide-5-mononitrate in angina pectoris patients evaluated
by exercise testing. J Cardiovasc Pharmacol 1989;13:320–3.
2. Watanabe H, Kakihana M, Ohtsuka S, Sugishita Y. Randomized,
double-blind, placebo-controlled study of the preventive effect of supplemental oral vitamin C
on attenuation of development of nitrate tolerance. J Am Coll Cardiol
1998;31:1323–9.
3. Bassenge E, Fink N, Skatchkov M, Fink B. Dietary supplement with
vitamin C prevents nitrate tolerance. J Clin Invest 1998;102:67–71.
4. Threlkeld DS, ed. Diuretics and Cardiovasculars, Antianginal Agents,
Nitrates. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and
Comparisons, Apr 1992, 143e.
5. Kosoglou T, Kazierad DJ, Schentag JJ, et al. Effect of food on the
oral bioavailability of isosorbide-5-mononitrate administered as an extended-release tablet.
J Clin Pharmacol 1995;35:151–8.
6. Threlkeld DS, ed. Diuretics and Cardiovasculars, Antianginal Agents,
Nitrates. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and
Comparisons, Apr 1992, 143e.
7. Threlkeld DS, ed. Diuretics and Cardiovasculars, Antianginal Agents,
Nitrates. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and
Comparisons, Apr 1992, 143e.