Also indexed as: Cardizem, Dilacor XR, Diltia XT, Tiazac
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.
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. |
DHEA
|
| Depletion or interference |
None known
|
| Side effect reduction/prevention |
None known
|
| Supportive interaction |
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
Dehydroepiandrosterone (DHEA)
Diltiazem has been shown to raise blood levels of DHEA and DHEA-sulfate in insulin-resistant,
obese men with high blood pressure.1
Interactions with Herbs
Pleurisy root
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 calcium channel
blockers.2
Interactions with Foods and Other Compounds
Food
Diltiazem may be taken with or without food.3 Sustained-release diltiazem products
should be swallowed whole, without opening, crushing, or chewing.4
In a study of healthy volunteers, ingestion of grapefruit juice at the same time as
diltiazem resulted in higher blood levels of the drug than when it was taken with
water.5 Studies with certain other medications suggest that grapefruit juice may
affect drug availability, even if it is consumed at a different time of the day. Therefore,
individuals taking diltiazem should probably avoid grapefruit and grapefruit juice.
References:1. Beer NA, Jakubowicz DJ, Beer RM, Nestler JE. Disparate effects of
insulin reduction with diltiazem on serum dehydroepiandrosterone sulfate levels in obese
hypertensive men and women. J Clin Endocrinol Metab 1994;79:1077–81.
2. Newall CA, Anderson LA, Phillipson JD. Herbal Medicines: A Guide
for Health-Care Professionals. London: Pharmaceutical Press, 1996, 213–4.
3. Du Souich P, Lery N, Lery L, et al. Influence of food on the
bioavailability of diltiazem and two of its metabolites following the administration of
conventional tablets and slow-release capsules. Biopharm Drug Dispos
1990;11:137–47.
4. Threlkeld DS, ed. Diuretics and Cardiovasculars, Calcium Channel
Blocking Agents. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and
Comparisons, Mar 1996, 149r–9t.
5. Christensen H, Asberg A, Holmboe AB, Berg KJ. Coadministration of
grapefruit juice increases systemic exposure of diltiazem in healthy volunteers. Eur J
Clin Pharmacol 2002;58:515–20.