Drug

Caffeine

Common brand names:

Keep Alert, No Doz, Vivarin

Caffeine is a central nervous system stimulant drug used as an aid to stay awake, for mental alertness due to fatigue, and as an adjunct with other drugs for pain relief. Caffeine is available alone as a nonprescription drug, in combination with other nonprescription drugs, and in prescription drug combinations for relief of pain and headache.

Summary of Interactions with Vitamins, Herbs, & Foods

  • Negative Interactions

    2

    • Caffeine

      Ephedra

      Potential Negative Interaction

      Until 2004, many herbal weight loss and quick energy products combined caffeine or caffeine-containing herbs with ephedra. This combination may lead to dangerously increased heart rate and blood pressure and should be avoided by people with heart conditions, hypertension, diabetes, or thyroid disease.

      Ephedra
      Caffeine
      ×
      1. Tyler VE. Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, Pharmaceutical Press, 1994, 88-9.

    • Caffeine

      Foods with Caffeine

      Potential Negative Interaction

      Caffeine is found in coffee, tea, soft drinks, and chocolate. To reduce side effects, people taking caffeine-containing drug products should limit their intake of caffeine-containing foods/beverages.

  • Supportive Interactions

    1

    • Caffeine

      Calcium

      Replenish Depleted Nutrients

      In 205 healthy postmenopausal women, caffeine consumption (three cups of coffee per day) was associated with bone loss in women with calcium intake of less than 800 mg per day. In a group of 980 postmenopausal women, lifetime caffeine intake equal to two cups of coffee per day was associated with decreased bone density in those who did not drink at least one glass of milk daily during most of their life. However, in 138 healthy postmenopausal women, long-term dietary caffeine (coffee) intake was not associated with bone density. Until more is known, postmenopausal women should limit caffeine consumption and consume a total of approximately 1,500 mg of calcium per day (from diet and supplements).

      Calcium
      Caffeine
      ×
      1. Harris SS, Dawson-Hughes B. Caffeine and bone loss in healthy postmenopausal women. Am J Clin Nutr 1994;60:573-8.
      2. Barrett-Connor E, Chang JC, Edelstein SL. Coffee-associated osteoporosis offset by daily milk consumption. The Rancho Bernardo Study. JAMA 1994;271:280-3.
      3. Lloyd T, Rollings N, Eggli DF, et al. Dietary caffeine intake and bone status of postmenopausal women. Am J Clin Nutr 1997;65:1826-30.

  • Explanation Required

    1

    • Caffeine

      Guaraná

      Needs Explanation

      Guaraná (Paullinia cupana) is a plant with a high caffeine content. Combining caffeine drug products and guaraná increases caffeine-induced side effects.

The Drug-Nutrient Interactions table may not include every possible interaction. Taking medicines with meals, on an empty stomach, or with alcohol may influence their effects. For details, refer to the manufacturers’ package information as these are not covered in this table. If you take medications, always discuss the potential risks and benefits of adding a new supplement with your doctor or pharmacist.

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