Food and drug interactions

There's a lot to pay attention to when you're managing medications for yourself or someone else—including knowing what foods and drugs may cause adverse side effects. Interactions between certain food and medications can be dangerous, so it’s always important to talk to your doctor about your diet or any changes in prescriptions. Listed below are some common medications and the foods that may cause adverse interactions.¹

MAOIs were the first type of antidepressant developed. There are four types of MAOIs approved by the Food and Drug Association (FDA): Isocarboxazid (Marplan), Phenelzine (Nardil), Selegiline (Emsam) and Tranylcypromine (Parnate). When taking MAOIs be careful to avoid foods with tyramine. Foods with tyramine include:

• aged cheese
• chianti wines
• chicken liver
• venison
• sauerkraut
• aged sausages like pepperoni and salami

Taking MAOIs with foods that contain tyramine may cause extremely high blood pressure, fever and, in rare circumstances, death.²

Taking medications that contain warfarin, an anticoagulant, in combination with large portions of foods high in vitamin K can potentially decrease the effectiveness of warfarin and increase the risk of blood clots. A few examples of foods with high amounts of vitamin K are:³

• spinach
• turnip greens
• broccoli

Drinking alcohol while taking large doses of acetaminophen-containing products, such as Tylenol^®, may cause liver damage. Drinking alcohol while taking metronidazole to treat infections may result in flushing, vomiting and increased heart rate.

Studies have shown that mixing certain medications with grapefruit or grapefruit juice can cause dangerously high levels of those medications in the blood, which may cause potentially life-threatening side effects.³ These medications include those used to treat depression, arrhythmia, transplants, seizures, high blood pressure and high cholesterol.

Taking osteoporosis medications and certain antibiotics along with calcium-fortified foods and drinks such as milk, orange juice, bread or antacids may reduce the effectiveness of these medications. Try to take your medication 2 hours before or 4 hours after consuming calcium-rich food and drinks.

Aspirin and other over-the-counter pain medications taken without food can cause stomach bleeding.