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Theophylline-Pseudoephed-GG

Drug Information

Summary of Interactions with Vitamins, Herbs, & Foods

What Are Nutrient Interactions
Types of interactions:BeneficialAdverseCheck

Replenish Depleted Nutrients

  • Magnesium

    Preliminary evidence indicates that theophylline can promote potassium and magnesium deficiency. Some doctors have noted a tendency for persons on theophylline to become deficient in these minerals. Therefore, supplementing with these minerals may be necessary during theophylline therapy. Consult with a doctor to make this determination.

  • Potassium

    Preliminary evidence indicates that theophylline can promote potassium and magnesium deficiency. Some doctors have noted a tendency for persons on theophylline to become deficient in these minerals. Therefore, supplementing with these minerals may be necessary during theophylline therapy. Consult with a doctor to make this determination.

  • Vitamin B6

    Theophyline has been associated with depressed serum vitamin B6 levels in children with asthma and adults with chronic obstructive pulmonary disease. In a short-term study of healthy adults, theophylline reduced serum vitamin B6 levels and supplementation with vitamin B6 (10 mg per day) normalized vitamin B6 levels. Some doctors believe that it makes sense for people taking this drug to accompany it with 10 mg of vitamin B6 per day.

Reduce Side Effects

  • none

Support Medicine

  • none

Reduces Effectiveness

  • St. John’s Wort

    One case study of a 42-year old asthmatic woman reported that taking 300 mg per day of St. John’s wort extract led to a significant decrease in blood levels of theophylline. Following discontinuation of St. John’s wort, the patient’s blood levels of theophylline returned to an acceptable therapeutic level. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. Until more is known, people taking theophylline should avoid St. John’s wort.

    The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence.

Potential Negative Interaction

  • Piperine is a chemical found in black peppers (Piper nigrum, Piper longum). A human study found that single doses of piperine could increase blood levels of theophylline. Hypothetically, such an elevation could lead to increased theophylline side effects or dose reductions without loss of drug efficacy. However, further study is required before such conclusions are made. People should not change the amount of theophylline taken without consulting their physician.

    The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence.

  • Large amounts of caffeine (a substance that is related to theophylline) may increase the activity and side effects of theophylline.Coffee, tea, colas, chocolate, guaraná, and some supplement products contain caffeine. Limiting intake of caffeine-containing beverages and products to small amounts will avoid this interaction.

    The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence.

Explanation Required

  • Herbs high in tannins can impair the absorption of theophylline. High-tannin herbs include green tea, black tea, uva ursi(Arctostaphylos uva-ursi), black walnut (Juglans nigra), red raspberry(Rubus idaeus), oak(Quercus spp.), and witch hazel(Hamamelis virginiana).

  • Low-carbohydrate, high-protein diets, charbroiled beef, and many types of cruciferous vegetables (broccoli, Brussels sprouts, cabbage, and cauliflower) can reduce theophylline activity. High-carbohydrate, low-protein diets can increase theophylline activity and side effects. Sustained-release forms of theophylline should be taken on an empty stomach and should not be crushed or chewed. Liquid and non-sustained release theophylline products are best taken on an empty stomach, but they may be taken with food if stomach upset occurs. People with questions about theophylline and food should ask their prescribing doctor or pharmacist.

    The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence.

  • Low-carbohydrate, high-protein diets, charbroiled beef, and many types of cruciferous vegetables (broccoli, Brussels sprouts, cabbage, and cauliflower) can reduce theophylline activity. High-carbohydrate, low-protein diets can increase theophylline activity and side effects. Sustained-release forms of theophylline should be taken on an empty stomach and should not be crushed or chewed. Liquid and non-sustained release theophylline products are best taken on an empty stomach, but they may be taken with food if stomach upset occurs. People with questions about theophylline and food should ask their prescribing doctor or pharmacist.

    The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence.

  • Low-carbohydrate, high-protein diets, charbroiled beef, and many types of cruciferous vegetables (broccoli, Brussels sprouts, cabbage, and cauliflower) can reduce theophylline activity. High-carbohydrate, low-protein diets can increase theophylline activity and side effects. Sustained-release forms of theophylline should be taken on an empty stomach and should not be crushed or chewed. Liquid and non-sustained release theophylline products are best taken on an empty stomach, but they may be taken with food if stomach upset occurs. People with questions about theophylline and food should ask their prescribing doctor or pharmacist.

    The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence.
  • Soy

    In a study of healthy volunteers given theophylline, ingesting daidzein (one of the major isoflavones in soy) in the amount of 200 mg twice a day for ten days inhibited the metabolism of theophylline, resulted in higher concentrations of the drug. The amount of daidzein used in this study was greater than what would be found in a normal portion of soy foods; it is not known whether consuming average amounts of soy would have a similar effect.

    The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence.
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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