Are You Aware of These Food-Drug Interactions?

Specific Medications Should not be Combined with Certain Foods

We have heard warnings against combining certain foods with certain medications. One common warning is to avoid drinking grapefruit juice with cholesterol medication. This juice can interact with other medicines too, both prescription and over-the-counter.

Given below are a list of foods and their effect on interaction with certain medicines.

Grapefruit Juice:  

Grapefruit juice interacts with medicines in quite many ways. One common way is by increasing the absorption of certain drugs — as is the case with some, but not all, cholesterol-lowering statins. It is better to avoid grapefruit juice if you are advised to take satins. It can also sometimes cause the body to metabolize drugs abnormally, resulting in lower or higher than normal blood levels of the drug. 

Antihistamines, blood pressure drugs, thyroid replacement drugs, birth control,stomach acid-blocking drugs and cough suppressant dextromethorphan are few medications that are altered in this way. Again, it is best to abstain or minimize the intake of grapefruit juice when taking these medications.

We may wonder what is wrong with grapefruit alone when compared to all other citrus juices. This is because, grapefruit juice has a class of compounds called furanocoumarins, which cause reactions that alter the characteristics of these medications. All other citrus juices, excluding Seville oranges and pummelo which are relatives of grapefruit, lack these compounds.

Green Leafy Vegetables: 

Blood-thinning drugs such as Coumadin (warfarin) intrude with vitamin K-dependent clotting factors. Green leafy vegetables are high in vitamin K and eating too much of these foods can decrease the ability of blood-thinners to prevent clotting. It becomes a problem when there is momentous increase or decrease in the intake of these foods, as it can alter the effectiveness of the medicine. So, it is better to eat these greens in balanced amounts instead of avoiding it altogether. Get in touch with a registered dietitian nutritionist at www.firsteatright.com to include balanced quantities of leafy greens veggies in your daily diet without altering the effectiveness of medication.

Natural Black Licorice (Glycyrrhiza)

Glycyrrhiza, a natural ingredient used to make black licorrice, can lead to a significant decrease in the amount of potassium in the body while increasing the retention of sodium. When this happens, the activity of digoxin, a medication used to treat heart failure, is magnified resulting in improper heart beat. 

This ingredient also reduces the potency of high blood pressure medicines. Also, individuals on Coumadin (warfarin) medication should be cautious of the effect of glycyrrhiza, as it can break down the drug there by increasing the body’s clotting mechanism. 

People on these medications should avoid consuming superfluous amounts of natural licorice. However, artificial-flavored black licorice can be consumed as it does not contain glycyrrhiza. 

Salt Substitutes 

Patients on digoxin medication for heart failure or ACE inhibitors for high blood pressure should take extra precaution with salt substitutes, as they usually replace the sodium content with potassium. This is because, with increased potassium intake, the cogency of digoxin decreases, leading to heart failure. In those individuals who consume ACE inhibitors, there might be a significant increase in blood potassium levels, as these drugs have the tendency to increase potassium.

It is not essential to forego salt substitutes altogether, but take extra caution when using these products. Patients having decreased kidney function should discuss the use of these salt substitutes with their healthcare experts. 

Tyramine-Containing Foods

Increased levels of the amino acid tyramine can result in high blood pressure. Numerous medications obstruct the breakdown of tyramine, including monoamine oxidase inhibitors (MAOIs) which treat depression and drugs used to treat the symptoms of Parkinson's disease. Doctors advise patients consuming these drugs to stay away from tyramine-rich foods. The list of these type of foods is huge and is not restricted to chocolate, aged and mature cheeses, smoked and aged/fermented meats, hot dogs, some processed lunch meats, fermented soy products and draft beers (canned and bottled beers are OK).

It is always better to consult with a physician and / or pharmacist about which foods and drugs patients should avoid or must be more cautious about, before starting on a new medication or taking a new over-the-counter drug.