Drug Interactions
Michael Jackson’s death has many of us wondering about drug interactions and how we can prevent future tragedies. There are three main types of drug interactions:
Drugs with food and beverages
Drugs with dietary supplements
Drugs with other drugs
Drugs with Food and Beverages
Drug interactions with food and beverages may cause your body to absorb too much or too little of a medication. Here are some common examples of drug interactions with food and beverages:
Alcohol: If you are taking any sort of medication, it’s recommended that you avoid alcohol, which can increase or decrease the effect of many drugs.
Grapefruit juice: Grapefruit juice shouldn’t be taken with certain blood pressure-lowering drugs or cyclosporine for the prevention of organ transplant rejection. That’s because grapefruit juice can cause higher levels of those medicines in your body, making it more likely that you will have side effects. The juice can also interact with the the anti-anxiety medicine Buspar (buspirone); the anti-malaria drugs Quinerva or Quinite (quinine); and Halcion (triazolam), a medication used to treat insomnia.
Licorice: Someone taking Lanoxin (digoxin), some forms of licorice may increase the risk for Lanoxin toxicity. Lanoxin is used to treat congestive heart failure and abnormal heart rhythms. Licorice may also reduce the effects of blood pressure drugs or diuretic (urine-producing) drugs, including Hydrodiuril (hydrochlorothiazide) and Aldactone (spironolactone).
Chocolate: MAO inhibitors are just one category of drugs that shouldn’t be consumed with excessive amounts of chocolate. The caffeine in chocolate can also interact with stimulant drugs such as Ritalin (methylphenidate), increasing their effect, or by decreasing the effect of sedatives such as Ambien (zolpidem).
Drugs with Dietary Supplements
Research has shown that 50 percent or more of American adults use dietary supplements on a regular basis. Dietary supplements include vitamins, minerals, amino acids, and herbs or botanicals. Examples of drug interactions with dietary supplements include:
St. John’s Wort: St. John’s Wort can reduce the blood level of medications such as Lanoxin, the cholesterol-lowering drugs Mevacor and Altocor (lovastatin), and the erectile dysfunction drug Viagra (sildenafil).
Vitamin E: Taking vitamin E with a blood-thinning medication such as Coumadin may cause an increased risk of bleeding.
Ginseng: This herb can interfere with the bleeding effects of Coumadin. In addition, ginseng can enhance the bleeding effects of heparin, aspirin, and nonsteroidal anti-inflammatory drugs such as ibuprofen, naproxen, and ketoprofen. Combining ginseng with MAO inhibitors such as Nardil or Parnate may cause headache, trouble sleeping, nervousness, and hyperactivity.
Ginkgo Biloba: High doses of the herb Ginkgo biloba could decrease the effectiveness of patients taking the following medications to control seizures: Tegretol, Equetro or Carbatrol (carbamazepine), and Depakote (valproic acid).
Drugs with Other Drugs
Two out of every three patients who visit a doctor leave with at least one prescription for medication. Close to 40 percent of the U.S. population receive prescriptions for four or more medications. And the rate of adverse drug reactions increases dramatically after a patient is on four or more medications. The FDA Consumer site has information on the latest recalls and interaction warnings. Examples of drug interactions with other drugs include:
Cordarone (amiodarone): FDA issued an alert in August 2008, warning patients about taking Cordarone to correct abnormal rhythms of the heart and the cholesterol-lowering drug Zocor (Simvastatin). Patients taking Zocor in doses higher than 20 mg while also taking Cordarone run the risk of developing a rare condition of muscle injury called rhabdomyolysis, which can lead to kidney failure or death.
Antihistamines: Over-the-counter (OTC) antihistamines are drugs that temporarily relieve a runny nose, or reduce sneezing, itching of the nose or throat, and itchy watery eyes. If you are taking sedatives, tranquilizers, or a prescription drug for high blood pressure or depression, you should check with a doctor or pharmacist before you start using antihistimines.
Tips to Avoid Problems
There are lots of things you can do to take prescription or over-the-counter (OTC) medications in a safe and responsible manner.
- Always read drug labels carefully.
- Learn about the warnings for all the drugs you take. The MedlinePlus database is a great place to start.
- Keep medications in their original containers so that 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.
- Check with your doctor or pharmacist before taking an OTC drug if you are taking any prescription medications.
- Use one pharmacy for all of your 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. Here is a good record from the FDA.
For more information on medication safety, visit our Medication page.
