Drug Interactions Involving Commonly Used Nonprescription Medications
Drug Interactions with Aspirin and Other Salicylates
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When prescribing a drug, your physician should take into account not only interactions between drugs but also how various drugs are going to interact with your unique health profile. If you have an irregular heartbeat and high blood pressure and your physician prescribes a diuretic that depletes magnesium, it will only make the irregular heartbeat worse. If you have asthma and high blood pressure and your physician prescribes an inhaler for the asthma, it could raise your blood pressure even more.
Here are the classes of drugs most often associated with serious interactions with other drugs, foods, and supplements:
• Benzodiazepines such as Ativan and Valium used as antidepressants
• Ephedrine and pseudoephedrine, found in many allergy, cough, cold, and decongestant medicines
• Heart drugs, including digoxin, calcium channel blockers, beta-blockers, and diuretics (especially the “loop” diuretics such as furosemide and the thiazide diuretics)
• H2 blockers such as cimetidine (Tagamet)
• MAOIs such as Marplan and Nardil used as antidepressants
• NSAIDs (nonsteroidal anti-inflammatory drugs, such as ibuprofen)
• Steroids (such as prednisone)
• Theophylline, an asthma drug
• Warfarin (Coumadin), a blood thinner
If you are taking any of these types of drugs, it is extremely important to be watchful at all times for drug interactions. For example, if you’re taking an MAOI and eat foods that are high in the amino acid tyrosine (i.e., avocados, aged cheese, not-quite-fresh liver or pâté, nuts, pickled foods, processed meats such as salami and bologna, wine, yogurt, soy sauce, and bananas), the interaction could cause life-threatening high blood pressure, severe headaches, dizziness, mental confusion, visual disturbances, and fever. MAOIs are outdated drugs that also react with dozens of over-the-counter drugs. These drugs should be taken only as a very last resort.
Top Drugs Implicated in Emergency Room Visits
Warfarin (blood thinner)
Insulin (diabetes)
Aspirin (heart/pain)
Clopidogrel (blood thinner/antiplatelet)
Digoxin (heart)
Metformin (diabetes)
Glyburide (diabetes)
Acetaminophen-hydrocodone (pain, e.g., Lorcet, Lortab, Vicodin, Zydone)
Phenytoin (seizures)
Glipizide (diabetes)
Levofloxacin (antibiotic)
Lisinopril (heart/ACE inhibitor)
Trimethoprim-sulfamethoxazole (antibiotic)
Furosemide (heart/loop diuretic)
Source: Budnitz, D. S., “Medication Use Leading to Emergency Department Visits for Adverse Drug Events in Older Adults,” Annals of Internal Medicine 147 (2007): 755–65.
Chapter 6
How to Read Drug Labels and Information Inserts
Every prescription drug comes with what is called a drug information insert or package insert. You will rarely see this when you fill a prescription at a pharmacy, but you should never take a drug without reading it first. Ask your pharmacist for a copy. The drug companies don’t really want you or the physician to read these inserts, because no drug looks good after you’ve read all its possible side effects and adverse reactions (so it is printed in extremely tiny, hard-to-read type). At the same pharmacy where you fill your prescriptions, you can buy a magnifying glass for a few dollars so you can read your drug insert. It will be one of the best investments you’ve ever made in your health.
You absolutely cannot count on the U.S. Food and Drug Administration (FDA), the drug company, your physician, or your pharmacist to keep you safe from dangerous drugs and their interactions. Your pharmacist is your greatest ally when it comes to protecting you from drugs, but ultimately it’s up to you to stay informed and to make decisions about your health. Your physician doesn’t want to tell you about possible drug side effects, because he or she has been programmed in medical school to believe that if you’re told about side effects, you’ll become a hypochondriac and get them. Unfortunately, that attitude is unlikely to change anytime soon. You are the best judge of whether you are having a bad reaction to a drug. Please trust your body’s feedback and pay attention to it.
Every year tens of thousands of people take home a prescription drug for a minor ailment and end up very ill, sometimes permanently, or even dead, because they weren’t aware of the risks associated with the drug. A dangerous side effect or adverse reaction may have happened in less than 1 percent of the people who took the drug in testing, but if you happen to be in that 1 percent, it could save your life to be informed.
For new drugs, the information listed on the package insert comes primarily from FDA-required studies on the drug. But don’t think that just because the drug company has spent tens of millions of dollars jumping through FDA-required hoops that means that the drug is well studied. In fact, many studies use patients in mental institutions, nursing homes, homeless shelters, universities, and other places with untypical test subjects. Anyone in a mental institution is already going to be thoroughly drugged, making any study results virtually useless because of drug interactions. Those in homeless shelters are often abusing street drugs or alcohol, again creating unpredictable reactions, not to mention a population impossible to follow up on. University students may or may not be taking drugs and using alcohol, but in any case they are generally young and healthy, unlike the majority of people who take prescription drugs. Another factor making drug studies less than meaningful is that few drugs are studied for more than three months, making long-term side effects unpredictable.
The Public Citizen Health Research Group, which publishes the book and newsletter Worst Pills, Best Pills, suggests avoiding any drug that hasn’t been on the market for at least seven years. Before that time, you are, in effect, a guinea pig for the FDA and the drug company.
Deciphering Your Drug Insert
The Physicians’ Desk Reference (PDR) is a large red volume that you’ve probably seen on the shelf in your physician’s office. It is updated every year, and in it is printed the drug information insert for nearly every prescription drug on the market. Thanks to the Internet, you now have free access to the same information. Simply put the name of your drug into a search engine, and you’ll find numerous listings for it. If the drug you’re researching has its own website, be sure to read the physician information, which is much more thorough than the patient information. In the Resources and Recommended Reading section at the back of this book you’ll find some suggestions for websites that list drug information and online medical dictionaries.
Here are the categories of information provided in the PDR and a translation of some of the medical terms that make the PDR difficult to understand without a medical dictionary.
• Brand name. Once the patent runs out on a drug it can be sold by almost anyone. The brand name of a drug is specific to the company that is packaging and selling it. For example, pseudoephedrine is the generic name of an antihistamine, but it is sold under the brand names Sudafed, Chlor Trimeton, Dimetapp, and others.
• Generic name. This is the name a drug is called regardless of its brand or trade name. For example, acetaminophen is the generic name for Tylenol, and ibuprofen is the generic name for Advil and Motrin.
• Form. How the drug is taken. Most drugs are taken as capsules, pills, tablets, or liquids. In the hospital, many drugs are delivered as liquids through an injection or IV.
• Description. This describes the drug in chemical terms, often with an accompanying molecular diagram. It also lists fillers, binders, dyes, and other nondrug ingredients in the medication. This is important if you are allergic to food dyes, preservatives, or even ingredients such as corn that may be used as a filler. If you find you are sniffling, sneezing, wheezing, coughing, or experiencing fatigue or puffiness after taki
ng a medication, it could be due to an allergic reaction to a preservative or food dye, especially the yellow and red dyes, which are used in the majority of prescription medications.
• Clinical pharmacology. This is a description of what the drug does in the human body. Most of these descriptions conclude with a paragraph stating that the action or mechanism of the drug is not fully understood. Always keep that in mind—even the drug company often doesn’t really know how the drug works.
• Indications and usage. This tells you what the drug is prescribed for. If your specific ailment isn’t listed here, that’s called an “unlabeled use,” meaning the drug hasn’t been studied or approved by the FDA for that use. Once a drug is approved by the FDA for any use, physicians are free to prescribe it for any reason they choose.
Physicians frequently prescribe drugs for unlabeled uses, and drug companies frequently cleverly market drugs for unprescribed uses even though they legally aren’t supposed to. For example, the antidepressant Prozac is now approved by the FDA for treating depression, obsessive-compulsive disorder, and bulimia, and it’s also now being sold under the name Sarafem for the treatment of premenstrual syndrome. For years before it was approved for anything but depression, it was marketed for obsessive-compulsive disorder and premenstrual syndrome. Currently, Prozac is being used off-label to treat obesity, and it’s being given to children without FDA approval. (Since most of the drugs available have not been tested on children, nearly every drug prescribed to a child is being used off-label.)
Another example of off-label drug use is the practice of using the stomach acid blocker Cytotec (misoprostol) for the induction of labor in pregnant women. If an obstetrician wants to hurry a woman’s labor along, he or she can insert tablets of Cytotec into her vagina and stimulate very powerful contractions. This practice is common despite the fact that it greatly increases the risk of uterine rupture.
The drug companies spread the word about these unlabeled uses through drug company reps. Another common ploy is to fund a so-called study showing that the drug works for an unlabeled use and then release the results of the study to the media (TV news programs such as “20/20” are favorites for this type of marketing). Another tactic they use is to find a few people who experienced a “cure” for the disease by taking the medication and then take those stories to the media. This type of media coverage, as well as articles that are “planted” in magazines by public relations companies or departments, creates what is known as patient demand. You see a story on a news program about the unlabeled use of the drug, and the next time you go to your physician you mention it. It’s a very effective form of marketing. You can pretty much assume that any media coverage a drug gets has been created through manufacturer marketing and public relations. If it’s negative coverage, chances are a competitor created it.
Don’t be overly concerned if your ailment isn’t listed—chances are the labeled use hasn’t been very well studied either!
• Contraindications. This is where the drugmaker is supposed to say, “If you have __________ (disease), don’t take this drug.” Most of the time what’s listed here is something useless like, “Do not take this drug if you have a known allergy or sensitivity to __________ (drug name)”—as if you would know that ahead of time.
• Warnings. This is where you want to pay close attention. This section lists a variety of conditions that might make taking the drug dangerous. For example, the warnings section for the drug Procardia (nifedipine) warns that it can cause “excessive hypotension” (low blood pressure), which can be life-threatening. It also warns of the possibility of increased angina, myocardial infarction (heart attack), a withdrawal syndrome, and congestive heart failure. Our guess is that only a handful of the hundreds of thousands of people taking this drug are ever aware of these very real dangers. If they weren’t real dangers, they would not be included. This is also the place to look for warnings about using the drug with patients who have renal or hepatic impairment, dysfunction, or disease. Renal refers to the kidneys, and hepatic refers to the liver. Nearly all prescription drugs are hard on your liver, but this type of warning should alert you to added risk.
• Precautions. This is another section of the drug insert where your physician may be warned about prescribing the drug to people with renal or hepatic dysfunction, or it may advise them to frequently monitor kidney and liver function. Again, a red flag should go up—this drug is particularly hard on those organs. This section also lists drug interactions. If you are taking any other type of drug, read this section carefully, and if you find you are already taking a drug on the list, do not take the new drug until you have spoken with your physician or your pharmacist about the interaction.
If the drug you’re taking has caused cancer, genetic mutations, or impaired fertility in laboratory animals, this is the place to find it. Physicians like to pooh-pooh this type of research, but we’d like you to take it very seriously. If the cancer, mutation, or impaired fertility wasn’t significant, it wouldn’t have made it onto the drug information insert. While rodents aren’t an ideal model of what happens in a human, it’s an accurate enough indicator to cause concern.
This is also where warnings about taking the drug if you’re pregnant show up. However, it’s safest to consider all drugs unsafe during pregnancy. Drugs should be completely avoided during pregnancy unless the mother’s or child’s life is at risk.
Drugs That Can Cause Incontinence
Medical Terms Frequently Found in Drug Information Inserts
• Adverse reactions. When a drug company is testing a drug on humans, it is required to record all the adverse reactions or side effects a patient has to it. The adverse reactions may have nothing to do with the drug, but there is no way of separating an authentic adverse reaction from a coincidental reaction. On the other hand, adverse reactions are notoriously underreported. For example, if a drug is reported to cause dizziness in 13 percent of the people taking it, it’s likely to be much higher than that.
The bottom line is that if you experience any of the side effects or adverse reactions listed on the drug insert, you should tell your physician. If the side effect is even remotely life threatening, get medical attention right away.
M.D.s have a way of making patients feel as if they are responsible for drug side effects and minimizing the discomfort they can cause. If this happens to you, please either stand up for yourself, have someone such as a spouse do it for you, or find another doctor. You should never have to suffer from drug side effects, nor should you ever allow your physician to get you onto the drug treadmill by prescribing new drugs to treat the side effects of the first or second one.
Drugs That Can Cause Photosensitivity
• Overdosage. This section gives the symptoms of an overdose of the drug and if available, an antidote to an overdose. Many heart drugs, such as ACE inhibitors, beta-blockers, digitalis drugs, and the blood-thinning drugs, can be fatal if levels are even a little bit too high. There are many factors that can raise levels of these drugs, including drug-drug interactions, drug-food interactions, alcohol consumption, and stress. Knowing the symptoms of an overdose can be lifesaving if you catch it early.
• Dosage and administration. This section lists the amounts the drug comes in and in what form it is delivered—for example, capsule, tablet, oral, liquid.
Generic and Brand Names of Commonly Used Drugs
(Not all brand names are listed.)
Abbreviations on Prescription Slips and Bottles
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Other Words You Should Know
It’s preferable not to take any prescription drug long-term, but if you do, it’s wise to purchase a medical dictionary and use it to look up words in the drug information insert that you don’t understand. You can find a paperback medical dictionary in almost any bookstore, and you’ll find suggestions for online medical dictionaries in “Resources and Recommended Reading” at the back of this book.
Know Your Generic Names
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br /> Throughout Part 2 of this book, you will find hundreds of drug names. Although in some cases both the generic name and the brand name will be listed, often only the generic name will be listed. If you are taking a generic version of your drug, it will often just be called by its generic name. But if not, you can usually find the generic name on your pill bottle or the container it came in. If the generic name is not on the bottle, ask your pharmacist to write it on. The generic name will also be found on the drug insert information, or you can find it online.
Chapter 7
Surgery, Drugs, and Nutrition: Minimizing the Damage and Maximizing Your Recovery
American physicians are generally way too eager to use the surgeon’s knife to carve up and cut out whatever they think is ailing you, at great expense to you and great profit to them and the hospitals they work for. Sometimes when you have a chronic illness, it may seem like having surgery will be a quick and easy end to the pain. But if you don’t address the problems that caused the pain in the first place, you’ll wind up sick again within a few months, with nothing to show for your surgery but a huge medical bill, a scar, and possibly a missing organ.
Of the 750,000 hysterectomies done every year, it is estimated that 650,000 of them are unnecessary. U.S. physicians perform some 300,000 cesareans a year, most of them unnecessary. Carving up men’s prostate glands started to be big business, but men caught on that it wasn’t necessary and squawked loudly, and the practice has rapidly declined. (Women need to learn to protest louder when mainstream medicine mistreats them.) Other surgeons’ favorites that are often unnecessary are procedures for gallstones and heart disease (especially bypass operations).
Prescription Alternatives Page 7
