Nifedipine is a calcium channel blocker used to treat angina pectoris and high blood pressure.
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: Adverse interaction—Avoid these supplements when taking this medication because taking them together may cause undesirable or dangerous results. | Pleurisy root* Tobacco* |
 Check: Other—Before taking any of these supplements or eating any of these foods with your medication, read this article in full for details. | Grapefruit juice Pomegranate juice* |
| Depletion or interference | None known |
| Side effect reduction/prevention | None known |
| Supportive interaction | None known |
| Reduced drug absorption/bioavailability | 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 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.1
Interactions with Foods and Other Compounds
Grapefruit juice
Ingestion of grapefruit juice has been shown to increase the absorption of felodipine (a drug similar in structure and action to that of nifedipine) and to increase the adverse effects of the medication in patients with hypertension. People taking nifedipine or similar drugs should not consume grapefruit juice or grapefruit, unless they have discussed it with their physician.2
Pomegranate juice
Pomegranate juice has been shown to inhibit the same enzyme that is inhibited by grapefruit juice.3 4 The degree of inhibition is about the same for each of these juices. Therefore, it would be reasonable to expect that pomegranate juice might interact with nifedipine in the same way that grapefruit juice does.
Food
Nifedipine may be taken with or without food.5 Nifedipine products should be swallowed whole, without crushing or chewing.6
Tobacco
In a double-blind study of ten cigarette smokers with angina treated with nifedipine for one week, angina episodes were significantly reduced during the nonsmoking phase compared to the smoking phase.7 People with angina taking nifedipine should not smoke tobacco.
References
1. Newall CA, Anderson LA, Phillipson JD. Herbal Medicines: A Guide for Health-Care Professionals. London: Pharmaceutical Press, 1996, 213–4.
2. Bailey DG, Malcolm J, Arnold O, Spence JD. Grapefuit Juice-Drug Interactions. Br J Clin Pharmacol 1998;46:101–110.
3. Sorokin AV, Duncan B, Panetta R, Thompson PD. Rhabdomyolysis associated with pomegranate juice consumption. Am J Cardiol 2006;98:705–6.
4. Summers KM. Potential drug-food interactions with pomegranate juice. Ann Pharmacother 2006;40:1472–3.
5. Reitberg DP, Love SJ, Quercia GT, Zinny MA. Effect of food on nifedipine pharmacokinetics. Clin Pharmacol Ther 1987;42:72–5.
6. Threlkeld DS, ed. Diuretics and Cardiovasculars, Calcium Channel Blocking Agents. In Facts and Comparisons Drug Information. St. Louis, MO: Facts and Comparisons, Mar 1996, 149m–9n.
7. Deanfield J, Wright C, Krikler S, et al. Cigarette smoking and the treatment of angina with propranolol, atenolol, and nifedipine. N Engl J Med 1984;310:951–4.
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2006-09-07
