The combination of certain foods and your medication(s) can affect how the drug is broken down, absorbed or metabolized in your liver. Whether you have just started on a new medication or you suddenly find your medication isn't working as effectively, I suggest checking to make sure your prescriptions are consumed away from the most common offending food interactions. A few tips:
Go for Berries Instead of Grapefruit: If you like to start off your morning with eggs and a side of grapefruit, you may want to rethink your breakfast. Grapefruit (juice and supplements) can interact with more than 50 prescription drugs -- ranging from cholesterol-lowering and heart medications to allergy and immunological drugs -- by inhibiting an enzyme in the intestine that breaks down the drug.
As a result, you end up getting a higher dose of a drug than anticipated, which can substantially increase the likelihood of side effects. Some types of oranges (Seville, Tangelo) can also have this affect.
Move your morning coffee (1 hour): The timing of your morning cup of java may pose more of a problem than you think, particularly if you consume it close to taking thyroid medication. In one small study, when a T4-based medication such as synthroid was swallowed with coffee/espresso, coffee lowered the average and peak incremental rise of thyroid hormone by up to 36 per cent.
If you take your medication upon waking up, then ideally you should wait 45 to 60 minutes before your cup of Joe. That doesn't mean, however, that you should switch to black tea instead. Research shows that it too can have an inhibitory effect on how certain drugs are metabolized by the liver. To play it safe, stick to drinking water with your meds.
Don't Fill Up on Fibre (2 hours): Fibre is probably the most common potential food interaction since it slows the rate that the stomach empties. This might leave you with a lower dose of medication than desired. I have had patients on thyroid mediation experience a dip in energy that corresponded with a boost in their fibre intake because they were unknowingly letting these two worlds collide.
In the aforementioned study on thyroid medication versus caffeine, they also included bran as a test agent and -- not surprisingly -- found it to interfere with thyroid absorption. To avoid any issues simply take any fiber supplements two hours away from any medications. A two-hour window will leave you feeling back to yourself. Or, for those on thyroid medication, another option is to take the medication before bed, and move your iron to lunch and your calcium to dinner to avoid the fiber/calcium/iron conundrum.
Steer clear of dairy (1-4 hours): Dairy is known to affect the absorption of iron supplements; and both dairy and iron supplements impact the absorption of certain medications, particularly thyroid meds. If you are taking all three, you may need to do some creative planning -- such as taking your thyroid drug first thing in the morning, iron at dinner (preferably with digestive enzymes and vitamin C to aid absorption) and calcium at bedtime (also preferably in combination with magnesium glycinate).
The calcium in dairy has also been found to interfere with some antibiotics (such as tetracyclines and ciprofloxacin) because it binds to the antibiotics in the stomach and forms an insoluble compound.
In turn, you get less of the active drug compound circulating in your bloodstream. In the case of dairy and antibiotics, separating it by 1-2 hours is sufficient. You may just need to have your prescription in one hand and a diet diary in the other to ensure there are no unwanted interactions.
Go Easy on The Alcohol: You have probably seen the warnings on your prescription bottle and these are there for good reason. Alcohol can affect antidepressants, antihistamines, sleeping pills, sedatives, and even some antibiotics. Mixing certain antibiotics, including Flagyl (metronidazole), Tindamax (tinidazole) and Bactrim (trimethoprim-sulfamethoxazole) with alcohol can increase the likelihood of more severe side effects including, headaches, cramps, nausea and vomiting (a science experiment gone bad in your stomach!). Meanwhile, a mix of aspirin or NSAIDs with alcohol can damage the gastric mucosal barrier and increase the risk of gastrointestinal bleeding.
Sometimes event the type of alcohol matters: One study published in the Journal of Agricultural and Food Chemistry found that more bitter-tasting beers reduced the effect of the cancer drug Tamoxifen, when compared with beers that were less hopped.
While all this may seem confusing, mixing meds and food doesn't have to be a guessing game. I recommend that you create a daily vitamin and medication dosing sheet with assistance from your health practitioner(s). Your dosing schedule should list what medications and vitamins are taken at what time (i.e. upon rising, breakfast, lunch, dinner or before bed) to avoid negative interactions as well as maximize absorption.
If you would like to complete a quick check of your possible interactions, here is a handy reference guide.