Over a million people are harmed every year by reactions to prescription drugs. Many of these are caused by interactions between incompatible medications.

Unfortunately, physicians are not always aware of these potential hazards. One study found that prescribers did poorly on a take-home test of which drug combinations should not be taken together (Drug Safety, June, 2008). Only one in five, for example, was aware that the anti-anxiety drug alprazolam (Xanax) is incompatible with the anti-fungal agent itraconazole (Sporanox).

It is not surprising that prescribers have a hard time remembering dangerous drug interactions. There are, after all, way too many hazardous combinations to memorize them all.

That’s why experts had hoped that electronic prescribing with a computer or smart phone would alert doctors to possible problems before they wrote a prescription. There is growing recognition, however, that technology alone is inadequate to protect patients from harm (Journal of Managed Care Pharmacy, Jan-Feb, 2012).

Doctors frequently ignore and override the drug interaction alerts that pop up on their computer systems (American Journal of Managed Care, Oct., 2007). Insiders refer to this as “alert fatigue” because physicians become desensitized to interaction warnings.

A study of discharge prescriptions reveals the seriousness of the problem and also a potential solution (Annals of Emergency Medicine, Feb. 2013). Researchers reviewed 674 prescriptions (roughly half) of all those written over a three-week period at a busy emergency department.

Nearly one fourth of the children’s prescriptions and eight percent of the adults’ medications had significant errors and posed a risk to patients. That was even after a review by electronic drug checks. In this investigation, pharmacists discovered the mistakes and checked with the prescribers, who admitted their errors and changed the medication.

Because children are so vulnerable to medication mistakes and drug interactions, Children’s Medical Center in Dallas has put 10 full-time pharmacists in the emergency department to review each prescription before it is dispensed. They review 20,000 prescriptions every week and prevent a significant number of interactions and other prescribing problems.

This is expensive, so very few hospitals use this effective strategy to double-check prescriptions. That’s why patients themselves need to be extra vigilant. A reader related this experience: “I had a very bad interaction from taking Gralise, tramadol and Cymbalta. I was told that I had serotonin syndrome.”

The pain reliever tramadol (Ultram) and the antidepressant duloxetine (Cymbalta) both work on the neurochemical serotonin and together they can cause serotonin syndrome. Symptoms of this life-threatening reaction include agitation, fever, sweating, uncontrollable muscle contractions, rapid heart rate and hallucinations. It can progress to coma and death. Gabapentin (Gralise) also interacts with both tramadol and Cymbalta, so the entire combination was risky.

You can learn more about how to protect yourself from such scary interactions through our book, Top Screwups Doctors Make and How to Avoid Them. You may think this can only happen to someone else. But if you are taking drugs such as Advil, Aleve, aspirin, warfarin, lisinopril, valsartan or ramipril, to name just a few, you need to be proactive in order to prevent a potentialy deadly drug interaction.

Here is a link to our book with its chapter on imcompatible combinations and our “Top 11 Tips for Preventing Dangeorus Drug Interactions.”

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  1. chill
    Reply

    Very well put, and I agree all the way!

  2. Aunt Caro
    Reply

    I use an app called Epocrates. The free version has enough information on drug effects, cautions, incompatibilities, etc. to be an effective quick reference for most of us.

  3. pp
    Reply

    In this world, your local pharmacist is your best friend. A good relationship with him or her is as important as that with your doctor!!! Talk with them about any new drug, and whatever else you are taking.

  4. LJ
    Reply

    Two websites I’ve used are http://www.drugs.com and http://www.askapatient.com.
    While it’s definitely in our best interest to be proactive in investigating prescription drugs before we begin taking them, it seems to me that this is yet another responsibility offloaded by doctors and the insurance companies that employ them. As consumers, we’re required to be experts in everything these days–or pay the consequences. It requires huge amounts of time spent online doing research. Why is it, in these times when our political representatives are so in favor of personal responsibility, that it seems so easy for all those professionals to abdicate it? Doesn’t personal responsibility apply to providers as well as recipients?

  5. PM
    Reply

    I had been taking Lipitor, experiencing shin splints and unable go on my regular walks without having to stop for extreme tiredness. Later I caught a cold and because of my husband’s illness he urged me to see a doctor. She prescribed levaquin. I asked if there were any side affects. I was assured there was none. I asked the druggist if there were side affects. Again I was told there weren’t any. Doctor and druggist both were aware I was taking Lipitor.
    I took seven of the eight doses of Levaquin. That night I awakened at midnight, went to the bathroom, sitting down when I experienced the most excruciating pain, I had fainted’, awakened to feel the cold bathtub, crawled back to bed one hour later. I went back to the doctor, my pulse racing. She ordered me to the ER. There I told the doctor I knew the cause, to just give me a Benadryl shot and let me go home and said I was allergic to Levaquin. They said they prescribe that to a lot of patients – that wasn’t the problem.
    I was taken to a battery of testing – chest x-ray, MRI!, etc. from 4:30 pm to 10:30 pm I was kept under protest. Finally, the ER doctor said, “We think you’re right.” They gave me the Benadryl and sent me home. My husband was in his hospital bed, my daughter rushed to our home after three hours of driving to care for us. You can understand my reluctance
    in taking drugs.

  6. HGB
    Reply

    I recently had spinal fusion surgery and was given Flexoril as a muscle relaxer. I also take Cymbalta. Unfortunately, I had not read the drug information that came with Cymbalta when it was first prescribed for me a year or so before. This hospitalization was 5 days and I received the drug during that time and two days afterwards.
    It was only when the visiting physical therapist took a close (she wanted to see all the containers of my meds) and entered them in her computer system that it was discovered these two drugs should not be given together.
    Neither my physician’s office nor the hospital’s pharmacy caught this conflict, nor had my physician who prescribed Cymbalta issued any warnings to me about the drug Flexoril. And, I must admit to having taken Flexoril on my own from an old prescription I had stored away before I was given Cymbalta.
    Fortunately, I had no ill effects and a substitute was prescribed.

  7. BJN
    Reply

    Great information, but ultimately it’s still MY responsibility to read the patient information that comes with a prescription. If unable to do so myself, then my advocate/representative should be told to check this for me.
    However, there will still be emergency situations in which meds are prescribed, and it’s nice to know that the professionals are being made aware of the problem.

  8. A.X.
    Reply

    As a patient (who’s thankfully not on any meds, but you never know what the future will bring), I’d like to be able to look up drug interactions myself and not rely on a flawed system getting this right. Couldn’t someone maybe put together some online resource where you type in the name of a drug and it pops up with what not to take it with or any other concerns? I know you can google the name of a drug and something like “side effects” or “cautions” or “warnings”, but the info from those searches is inconsistent. Seems like it couldn’t be too big a deal to assemble a database-like page like this.

  9. Jesse
    Reply

    Drugs are too dangerous to be put in the hands of doctors. Computer programs showing all drugs taken by a patient should approve each new prescription, and also check the reason for the prescription.
    I went to a new internist who was 12 years in practice and ten minutes into the office visit said I should be on an injection for osteoporosis and also a proton pump inhibitor, and she would prescribe it. I asked her why did I need the osteoporosis annual inject as I don’t have osteoporosis. She said because of my age. I am 70. I asked why would I need a PPI, she said because I had left sided chest pains relieved by belching two nights the week before and it was probably gastric reflux. I said I would like to wait and see if I ever have it again. She replied, “I can see you are going to be a difficult patient.” I would not take drugs for problems I didn’t have. The injection is around $1,800 I was told. The PPI probably about $100 a month. Those two drugs are dangerous for my health and for my bank account.
    Then she wanted to order a bone scan for osteoporosis although I had one two years ago and it was normal. All I wanted was to establish a relationship with a new internist. All my good doctors are retiring. The new doctor is from India and trained there and perhaps useless prescriptions are the fashion there. Few internists take Medicare patients here, all have either retired or gone to “boutique” practice where you pays an extortion fee of arouund $2,000 a year and all you get is one annual office visit. All the other office visits, EKGs, labs, scans are regular price. And you get the doctor’s email address. I have all three of my other doctors’ email addresses because they like to speed things up with emails. They like to give the answers themselves rather than relay them through a third person.
    If more and more patients are learning about the dangers of drugs and the over-prescribing, why don’t the doctors catch on and back off the pill pushing? Do the drug companies still give perks, rewards, free airlines tickets, dinners, huge speaker fees, etc. to doctors who push their pills? I know drug companies get print outs from pharmacies showing which doctors are prescribing their pills. That should be against the law. A local newspaper listed the dollar amount local doctors received and some received up to $300,000 a year for “speaker fees” or “consulting fees.” So I guess this pay off is a matter of public record. Perhaps patients should check online and learn how much their doctor is being paid by drug companies.

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