Supplements or food -> drug interactions

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    Food Interactions
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Discussion Overview

The discussion revolves around the interactions between dietary supplements, foods, and drugs, particularly focusing on how certain supplements may affect the efficacy or safety of medications. It includes examples of known interactions and the mechanisms behind them, as well as personal experiences with these interactions.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants note that supplements are widely used and may interact with foods or drugs, citing Coenzyme Q10 as an example for statin-induced myalgia.
  • Grapefruit is highlighted as a problematic food that can interact negatively with certain medications, particularly statins, due to its effect on drug metabolism.
  • One participant questions the specific reasons why grapefruit increases the rate of uptake for various drugs.
  • A source is provided explaining that grapefruit juice inhibits the CYP3A4 enzyme, which can lead to increased bioavailability of certain drugs, potentially resulting in overdose effects.
  • Concerns are raised about the reliability of drug interaction checkers, particularly when using outdated web browsers, as one participant experienced misleading results regarding Levothyroxine and Calcium Carbonate interactions.

Areas of Agreement / Disagreement

Participants express a general agreement on the existence of interactions between supplements, foods, and drugs, particularly regarding grapefruit. However, there are differing views on the reliability of drug interaction checkers and the implications of these interactions, indicating that the discussion remains unresolved in certain aspects.

Contextual Notes

Limitations include the potential for outdated information from interaction checkers and the need for updated browser technology to ensure accurate results. The discussion also reflects varying levels of understanding regarding the biochemical mechanisms of interactions.

Who May Find This Useful

This discussion may be useful for individuals interested in pharmacology, healthcare professionals, and those taking multiple supplements or medications who are concerned about potential interactions.

jim mcnamara
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TL;DR
https://reference.medscape.com/drug-interactionchecker finds references for possible interactions of drugs and supplements
Since supplement sales in North America are multi-billion dollar enterprises and many people take one or more supplements, this is a useful way to find out if there is a problem with a supplement interacting with a food or a drug. Supplements are sometimes prescribed, like Coenzyme Q10 for statin induced myalgia.

Examples: some statins and grapefruit are a bad combination, bisacodyl (a laxative) is inactivated when taken with milk.

The interaction can be be to block, to reduce, or to stimulate the drug response.

https://reference.medscape.com/drug-interactionchecker

It is interesting to play with. It has some limits.
 
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Grapefruit is a notoriously bad actor for increasing the rate of uptake for a bunch of drugs...anybody know why?
 
You asked
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.669.7074&rep=rep1&type=pdf
It is well known that grapefruits and grapefruit juice (GFJ) cause clinically important inhibition of the activity of intestinal CYP3A subfamily, mainly of the CYP3A4 form, and thus increases the oral bioavailability of many CYP3A4 substrates that undergo high presystemic metabolism even if consumed in normal quantities
Short answer: it speeds up the effects of an enzyme group. Which in turn increases the absorption rate of several groups of chemically similar drugs. And speeds up their biochemical effects. Sometimes dangerously.

Think: overdose

This is the opposite of blocking, the result is like taking too many meds orally at one time. From taking the correct dose.
 
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If you are running an old browser, DO NOT BELIEVE THE GIVEN RESPONSE OF 'No Result' or 'No Interactions Found'.

I tried various combinations of Levothyroxine with Calcium Carbonate and received 'No Result' and 'No Interactions Found' using Firefox 43.0.1.

The information sheet that comes with Levothyroxine specifically warns against that combination.
 
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