Drug And Food Interactions: More Common Than You Think
The headline sounded too good to be true. Scientists were reporting that the old-fashioned licorice stick contains a natural substance called amorfrutins that not only lowers blood sugar but also reduces inflammation.
Great news, right? Not if you’re taking the heart medication Lanoxin, also known as digoxin. In that case, regularly snacking on even a modest amount of licorice could increase your risk for developing toxic levels of that drug. The resulting side effects could range from confusion and nausea to heart palpitations, decreased urine output and respiratory problems.
Food and drug interactions are much more common than most people realize. Many people on prescription drugs probably already know it’s a bad idea to drink alcohol, which can interfere with many medications. But foods as seemingly innocuous as sausage and cheddar cheese can cause dangerous side effects for those taking certain types of antidepressants.
Even some apparently healthy choices, such as grapefruit and pomegranate, can be dangerous if you’re taking statin-based cholesterol medications such as Lipitor, Mevavor, or Zocor. And leafy green vegetables such as kale and spinach, which contain high levels of Vitamin K, can reduce the effectiveness of blood thinners prescribed for stroke prevention.
This type of information is especially important for people with diabetes, who may be taking multiple medications to manage potentially related conditions such as cholesterol, blood pressure, and heart conditions.
Just because the conditions are related, however, doesn’t mean the drugs used to treat them work in concert. A drug called Metoprolol, for instance, a beta blocker used to treat angina and high blood pressure, may make it harder to tell when your blood sugar levels are low.
Adding the chemical compounds in foods to the mix can complicate things even further. Foods high in carbs and sugar are an obvious no-no for those diagnosed with type 2 diabetes. But chocoholics who have trouble adapting to a diabetic diet are at even greater risk if they “slip up” while taking a class of antidepressants called MAO inhibitors.
These types of drugs, such as Nardil and Parnate, interfere with the body’s ability to break down a substance called tyramine in foods such as chocolate, cheese, and salami. A buildup of tyramine in the body causes blood vessels to narrow, leading to blood pressure spikes, severe headaches, and even internal bleeding.
Multiple Prescriptions Magnify the Problem
With one prescription, it’s easier to pay attention to the specific instructions for that particular drug. MAO inhibitors, for instance, come with specific dietary guidelines, that spell out what foods are safe. Which should be minimized, and which should be avoided altogether.
But if you’re juggling multiple prescriptions, it becomes much more difficult to keep everything straight.
“The rate of adverse drug reactions increases dramatically after a patient is on four or more medications,” reports the Food and Drug Administration on its website. And that applies to an increasingly large number of Americans – nearly 40 percent of U.S. adults, according to the FDA.
The stakes are high: There are more than 2 million “serious” adverse drug reactions reported each year, including 100,000 deaths. In fact, ADRs, as they’re called, are the fourth leading cause of death in this country, ranking higher than pulmonary disease, diabetes, pneumonia, and auto accidents.
“Many adverse drug effects can be attributed to drug interactions,” reported a study presented at the American Medical Informatics Association’s 2010 symposium. Its authors estimated that perhaps half of all such cases are caused by one drug interfering with another.
And that doesn’t even take into consideration the two other primary types of drug interactions: those that occur in conjunction with food and dietary supplements, which are even harder to track.
One of the most common drug interactions to be aware of, according to the FDA, is when people on blood pressure medication use an antihistamine to battle cold symptoms. The combination can cause a person’s blood pressure to rise and may also speed up the heart rate.
A much more dangerous example of a drug interacting with another drug is the potentially fatal combination of Cordarone, which is used to correct abnormal heart rhythms, used in conjunction with the cholesterol medication Zocor. According to an FDA alert issued in 2008, such patients ran the risk of developing a rare internal muscle injury that could lead to kidney failure or even death.
“Cordarone also can inhibit or reduce the effect of the blood thinner Coumadin,” According to Shiew-Mei Huang, deputy director of the FDA’s Office of Clinical Pharmacology. “So if you’re using Cordarone, you may need to reduce the amount of Coumadin you’re taking.”
These days many websites such as the Mayo Clinic, Web MD, and even Walgreen’s provide a tool called an online drug reaction checker in which people can simply type in the various drugs they’re taking and see if there are any issues to be concerned about.
However, all of these sites print disclaimers warning that patients should never use this information to make decisions about what medications to use or stop using. They are simply intended to help people have better informed discussions with their doctor.
Interactions with Dietary Supplements
More than half of American adults use dietary supplements regularly, according to the National Institutes of Health’s Office of Dietary Supplements. This includes vitamins, minerals, amino acids, herbs, and botanicals.
According to the FDA, the supplements to be especially aware of if you’re on multiple medications are Vitamin E, ginseng, ginkgo biloba, and St. John’s Wort (hypericum perforatum).
Vitamin E taken in conjunction with blood-thinners such as Coumadin can increase the risk of bleeding, the FDA says while ginseng can reduce the effectiveness of Coumadin. However, ginseng can increase the bleeding risk of other drugs such as heparin, aspirin, ibuprofen, naproxen, and ketoprofen.
St. John’s Wort activates certain liver enzymes that can reduce the effectiveness of drugs such as Lanoxin, the cholesterol drugs Mevacor and Altocor, and the erectile dysfunction drug Viagra.
Ginkgo biloba taken in high doses can impair the effectiveness of antiseizure drugs such as Tegretol and Carbatrol.
However, if you are taking nutritional supplements that don’t appear on this list, that doesn’t mean you’re not at risk. Discuss the usage of all dietary supplements with your doctor, who can check that list against your prescriptions.
Food Drug Interactions
The most common food and beverage interactions, according to the FDA, are caused by alcohol, grapefruit juice, chocolate, and licorice.
Licorice? Now wait a minute. What about that study out of Germany, widely reported in 2012, that suggested the old-fashioned candy with the built-in amorfrutins had the potential to help fight type 2 diabetes?
The key word there, it turns out, is potential. Scientists at the Max Planck Institute of Molecular Genetics in Berlin did show that amorfrutins such as those found in licorice helped reduce both blood sugar levels and inflammation in diabetic mice. The lower glucose levels prevented the development of insulin resistance.
The German research team also discovered that amorfrutins. Named after the fruit of the Amorpha Fruticosa bush, which also contains this substance – kept the mice from developing a fatty liver, which is a common problem associated with diabetes and a diet rich in fat. The amorfrutin molecules help to activate genes that process fatty acids and gluclose within the blood.
The trouble is, scientists say, the amount of amorfrutin molecules found in a piece of licorice candy is much too low to cause the same helpful effects in diabetic humans as it did in mice.
Further studies are ongoing. But in the meantime, it would be a serious mistake for those with type 2 diabetes to begin routinely snacking on licorice. In addition to concerns about sugar, carbs, and a possible interaction with the heart medication Lanoxin, licorice can also reduce the effectiveness of some blood pressure and diuretic drugs, including Hydrodiuril and Aldactone.
Tips to Ward Off Problems
Trying to control your diabetes can seem overwhelming even before you take into consideration all the different interactions that can occur with multiple medications. The good news is if you stay in good communication with your doctor you can avoid most problems and come up with a drug combination and diet that works best for you.
If you follow these simple tips from the American Heart Association, you should avoid most problems:
• _Keep medications in their original containers so you can easily identify them.
• _Ask your doctor what you need to avoid when you are prescribed a new medication. Ask about food, beverages, dietary supplements, and other drugs.
• _Always read drug labels carefully and learn about the warnings for all the drugs you take.
• _Check with your doctor or pharmacist before taking an OTC drug if you are taking any prescription medications.
• _Use one pharmacy for your entire drug needs.
• _Keep all of your health care professionals informed about everything that you take.
• _Keep a record of all prescription drugs, OTC drugs, and dietary supplements (including herbs) that you take. Try to keep this list with you at all times, but especially when you go on any medical appointment.