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What you eat or drink can affect the medicine you take. Sometimes, when certain foods or beverages mix with certain medicines, the drugs don't work as well as they should. Other times, the interactions can make the drugs more potent or cause potentially dangerous side effects.
Here are a few common examples of potential interactions from the U.S. Food and Drug Administration, the American Dietetic Association and other experts:
Grapefruit juice
Mixing this juice with some blood pressure drugs and other medicines can increase the medication level in the body. This can raise the risk of side effects.
Drugs that may interact with grapefruit juice include:
* Blood pressure pills, including felodipine (Plendil) and nifedipine (Procardia).
* Cholesterol-lowering medicines, such as atorvastatin (Lipitor) and simvastatin (Zocor).
* Antiarrhythmia drugs, including amiodarone (Cordarone) and disopyramide (Norpace).
* Gout medication, colchicine (Colcrys)
* Erectile dysfunction, sildenafil (Viagra)
Often, other drugs are available to treat these conditions. If you want to continue to drink grapefruit juice, ask your doctor if another medication would work for you.
Licorice
In some instances, licorice can block the effects of drugs used to treat heart conditions, or it can cause the drugs to rise to dangerously high levels in the blood.
For example, licorice may cause digoxin (Lanoxin), taken for congestive heart failure or arrhythmia, to become toxic.
Licorice may reduce the effects of other heart medicines such as hydrochlorothiazide or spironolactone (Aldactone).
Fiber
Foods high in fiber and some fiber supplements can interact with certain diabetes medications to decrease their effectiveness.
For instance, metformin (Glucophage) reduces the amount of glucose the body produces. But when taken with large amounts of fiber, metformin levels can drop, making the drug less effective.
Chocolate
It can increase the effects of stimulant drugs like methylphenidate (Ritalin) or decrease the effect of sedatives like zolpidem (Ambien).
Other interactions
Blood thinner Warfarin (Coumadin), prescribed to decrease the chances of stroke in people with heart problems, reacts with a variety of foods.
Eating more than moderate amounts of green, leafy vegetables, green tea, or some soy products can boost vitamin K levels and make warfarin less effective.
Too much vitamin E, cranberry juice, onions or garlic has the opposite effect on the drug.
Avoiding interactions
If you're concerned about the potential effects of foods or drinks on your medications, here are some steps you can take:
* Talk to your doctor or pharmacist before taking new over-the-counter or prescription medicines. Ask if there are any food or drink interactions you should know about.
* Keep a record of what you take, including prescription and nonprescription drugs, dietary supplements and herbal products. Review the list regularly with your doctor.
* Carefully read drug labels and any accompanying information, and take medicines as directed.
* Be cautious if you plan to drink alcohol. It can react with a number of different medicines.
Just because you need to take certain medications doesn't necessarily mean you have to avoid favorite foods or beverages that may interact with those drugs.
Your doctor may be able to prescribe a different dosage or alternate medicine to manage your condition.
