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
Avoid: Reduced drug absorption/bioavailability—Avoid these supplements
when taking this medication since the supplement may decrease the absorption and/or activity
of the medication in the body.
Avoid: Adverse interaction—Avoid these supplements when taking this
medication because taking them together may cause undesirable or dangerous results.
|Depletion or interference
|Side effect reduction/prevention
An asterisk (*) next to an item in the summary indicates that the
interaction is supported only by weak, fragmentary, and/or contradictory scientific
Interactions with Dietary Supplements
Some beta-adrenergic blockers (called “nonselective” beta blockers) decrease the
uptake of potassium from the blood into the cells,1 leading to excess potassium in
the blood, a potentially dangerous condition known as hyperkalemia.2 People taking
beta-blockers should therefore avoid taking potassium supplements, or eating large quantities
of fruit (for example, bananas), unless directed to do so by their
Interactions with Herbs
As pleurisy root and other plants in the Aesclepius genus contain cardiac glycosides,
it is best to avoid use of pleurisy root with heart medications such as
Interaction with Foods and Other Compounds
Taking acebutolol with food slows the rate of absorption and reduces the maximum blood levels
of the drug, though overall absorption is not affected.4 However, the blood level
of an active breakdown product of acebutolol is reduced.5 Though the activity of
acebutolol is affected by food, people taking the drug on a daily basis are not likely to
experience a reduction in the effectiveness of the drug if it is taken with a meal.
In a study of healthy volunteers, drinking 200 ml of grapefruit juice at the same time as
taking acebutolol caused a small decrease in blood levels of the drug by interfering with its
absorption.6 Although the researchers who performed this study felt that the effect
was unlikely to be clinically significant in most cases, it would seem prudent not to take
grapefruit juice at the same time as acebutolol.
1. Rosa RM, Silva P, Young JB, et al. Adrenergic modulation of extrarenal
potassium disposal. N Engl J Med 1980;302:431–4.
2. Lundborg P. The effect of adrenergic blockade on potassium
concentrations in different conditions. Acta Med Scand Suppl 1983;672:121–6
3. Newall CA, Anderson LA, Phillipson JD. Herbal Medicines: A Guide
for Health-Care Professionals. London: Pharmaceutical Press, 1996, 213–4.
4. Sifton DW, ed. Physicians Desk Reference. Montvale. NJ:
Medical Economics Company, Inc., 2000, 3317–9.
5. Zaman R, Wilkins MR, Kendall MJ, Jack DB. The effect of food and
alcohol on the pharmacokinetics of acebutolol and its metabolite, diacetolol. Biopharm
Drug Dispos 1984;5:91–5.
6. Lilja JJ, Raaska K, Neuvonen PJ. Effects of grapefruit juice on the
pharmacokinetics of acebutolol. Br J Clin Pharmacol 2005;60:659–63.