Use Caution Mixing Drugs and Food – Grapefruit interacts with certain drugs and increases their level, causing dangerous side effects.

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“Dear Pharmacist,

My doctor told me to avoid grapefruit juice with my medicine. I take thyroid hormone along with medication for heartburn, cholesterol and depression. Are there any other foods or beverages that could be dangerous with these drugs?”
—A.M., Ft. Lauderdale, Florida

Answer: Great question! Many people taking medications unknowingly eat foods that could cause serious interactions with the drugs. For example, it’s possible that eating cheese with MAO drugs used for depression could kill you. Coffee with some SSRI antidepressants could raise blood pressure and increase heart rate. Grapefruit spikes the levels of many medications, including some statin drugs used for cholesterol management.

If you take thyroid medicine, you should space your calcium supplements or dairy at least 2 hours away from your medication. Go easy on those delicious vegetables like broccoli, Brussels sprouts and cauliflower because they crash your thyroid levels. Soy lowers thyroid hormone too, so if you are prone to thyroid problems, maybe pass on the tofu and soy milk.

Here are other helpful tips:

Heartburn medication such as Prilosec OTC or Zantac should not be combined with coffee (decaf or regular). The coffee reduces pressure on the esophageal sphincter, causing more reflux.

Arthritis medicine like ibuprofen and Celebrex should not be combined with alcohol because you can increase your risk of GI bleeding and liver damage.

Diabetic medication should not be taken within 2 hours of fiber supplements or bran cereal because they may decrease drug absorption.

Some diuretics (spironolactone) cause your body to hold on to potassium, so avoid salt substitutes which contain potassium.

Digoxin used for heart failure should not be taken with oatmeal or bran cereal because the combination can cause life-threatening arrhythmias.

Painkillers like Vicodin or Percocet won’t work as well if you smoke because smoking causes faster clearance of the drug. It doesn’t get a good chance to work.

Sex pills can cause lightheadedness and dizziness. So can alcohol, so skip the Margarita if you take erectile dysfunction drugs such as Viagra and Cialis.

There are many more important interactions between food and medicine, and it’s very difficult to find this information. I think this information is incredibly important to your safety and well-being, which is why I’ve written a new easy-to-read book called “Drug Muggers: How To Keep Your Medicine From Stealing the Life Out of You!

The book includes a very large section on drug-food-herb interactions. You’ll also learn how to pick a high quality vitamin and what nutrient deficiency might be causing those leg cramps, nerve pain, arrhythmias, headaches, skin problems and dozens of other medical conditions. You can easily find out what vitamin or mineral is being mugged from your body by your medications or lifestyle choices (which results in side effects or new symptoms). “Drug Muggers” is available at and this website. CLICK HERE for more information.

Did You Know?
The B vitamin “niacin” can help improve blood flow and ease symptoms of Reynaud’s disease during the colder seasons.