20 Most Common Medical Mistakes in the U.S.

Mistakes will happen, even in places where they shouldn’t – like the hospital.

Medical mistakes not only injure more people than you think, they can be deadly. Recent research shows that—after heart disease and cancer—medical mistakes are the third leading cause of death in the US. More than accidents, strokes, lung disease and Alzheimer’s.

Medical mistakes can and do happen virtually anywhere. In hospitals, clinics, doctors’ offices, surgery centers, nursing homes, pharmacies, and patients’ homes. From nurses giving the wrong meds to the wrong patient, too much oxygen, too many transfusions, and surgeons removing the wrong body parts or leaving surgical equipment in a person’s body after an operation.

Each year, more than 200,000 people die from preventable medical mistakes, and up to 20 times more suffer from the side effects of medical mistakes but don’t actually die from them.


Many medical mistakes are caused by misdiagnosis. A wrong diagnosis can lead to the wrong treatment or a delay in treatment and it often has other severe consequences, mostly because the actual problem goes unchecked and untreated. Not receiving a proper and accurate diagnosis can also be dangerous.

It’s important to understand what symptoms and conditions you have, and not just do what most people do when they are asked to complete a form: hastily check-off a list of things that you don’t have.

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Unnecessary tests and deadly procedures

Studies show that $700 billion is spent every year on unnecessary tests and treatments. Not only is it an expensive waste of money but they are risky medical mistakes.

For example, CT scans are proven to increase the lifetime risk of cancer. Dyes from CTs and MRIs can cause kidney failure. Even a simple blood test can cause infection and other side effects, especially in the elderly, very young, and those with compromised immune systems.

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Medication mistakes

The wrong drug, the wrong dose, similar drug names, similar drug dosages and bad drug combinations can cause bad reactions and serious medical mistakes. More than 30 million Americans are victims of medication mistakes every year, at a cost of $3.5 billion.

The mistakes get even worse when patients are in-hospital. Over 60% of hospitalized patients miss their regular medication while they are in the hospital and, on average, 6.8 medications per patient are left out.

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Rx confusion

Medical mistakes caused by drug interactions are harmful. Most people rely on pharmacists deciphering the doctor’s scribbled note and preparing the specific prescription. But they neglect to tell the pharmacist about the other self-prescribed things they’re taking. Like the over the counter pain, headache and sleeping pills, remedies and supplements.

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Nasty (and fatal) allergies

Medical questionnaire forms have always included a space to write down allergies, although most people take them for granted. In tens of thousands of cases patients are routinely getting medications to which they didn’t realize (or they forgot) they were allergic.

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Hospitals and clinics seem clean and bright but it is well documented that they are among the most notorious places to get infections. Patients check in with various overlooked or undeclared infections. The staff get contaminated. And many patients already have weakened immune systems. According to the Centers for Disease Control and Prevention (CDC) contracting some type of health care facility infection affects 1.7 million people every year.

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OR mistakes

There are volumes of unbelievable and wild operating room surgery-mistake stories. Doctors operating on the wrong limb, removing the wrong leg or breast or kidney from the wrong patient. Drips and solutions meant to go into stomach tubes accidentally going into chest tubes, causing serious infections. Air bubbles in IV catheters, causing strokes. Scary stuff.

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Surgical souvenirs

It sounds exaggerated but it is a surprisingly common medical mistake. Surgical tools and other surprises are left inside the patient a lot more frequently than some think.

When operating room staff don’t properly count equipment before, during and after a surgical procedure, patients soon experience sudden pain, fever and swelling. It’s often a sign that scalpels, scissors, clamps, retractors and other surgical tools or wipes and sponges (which can sometimes fill up with blood and mistakenly show up as bodily tissues) were accidentally forgotten inside the body during the surgery.

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Waking up during surgery

If you receive a too-low dose of anesthesia, it may be an unusual medical mistake. Your brain may be “awake” even while your body appears to be anesthetized. Even if you can’t move your muscles and you’re unable to move or speak, you may still actually feel the surgery taking place.

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Every year, 500,000 patients fall while in the hospital. Many random accidents happen due to glitches with medical devices like monitors, drips and portable racks and stands. Clean hospital floors are often slippery for patients with mobility issues like broken legs, walkers or canes. Falls also frequently happen with unpredictable reactions to new drugs. Some 10 percent of falls for the elderly occur in hospitals.

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Too many blood transfusions

Red blood cell transfusions are one of the most common procedures in U.S. hospitals. Beware! Nearly 60 percent of transfusions are considered “inappropriate” and research shows the more blood cells a patient receives, the higher the risk for disease, and even death.

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Birth injuries

Giving birth is a joy, but it can trigger medical mistakes. Various medical mistakes and complications can happen. Women most at risk include those with large babies, premature babies and prolonged labor.

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Oxygen as a risk

Doctors caution that oxygen is like a drug and can be a medical mistake. Too much is not good, and too little isn’t good, either. There are numerous potential medical risks, such as too much oxygen given to premature babies causing blindness.

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Lab mistakes

Clinic and hospital labs do a mind-boggling number of tests on many patients. The testing is usually done in one lab. Faulty labeling or faulty test results and faulty readings can cause many medical mistakes. Dangerously wrong diagnoses get made, causing wrong treatments, while the initial disease continues untreated. Some common types of lab mistakes include blood tests and MRI or CT scans processed wrong, samples labelled incorrectly and test results misinterpreted.

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Missed warning signs

There are usually only minutes to show-up—and do something about—warning signs. Some common warning signs are changes in heart rate, blood pressure and other vital measurements. Ignoring the warning signs, or missing them entirely, can lead to serious medical mistakes and irreversible damage.

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Treatment mistakes

Even when the diagnosis is correct, common medical mistakes can still happen during treatment. Many doctors have been practicing for decades and it’s not unusual that they may be used to out of date procedures, because they are used to doing it a certain way. Don’t be shy! Ask about alternatives.

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Follow up care

Non-compliance and ignoring details of follow-up care are frequent causes of various medical mistakes. It’s important to understand and follow directions and instructions after the hospital or clinic visit.

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Bad communication

Common medical mistakes are caused by poor communication between doctor and patient. Going to the same doctor for years doesn’t necessarily mean the doctor knows or remembers everything about the patient.

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Waiting until it’s too late

Due to money and healthcare costs, nerves or just old-fashioned procrastination, some patients strategize that they can save money and wait for problems to go away by putting off doctor’s visits. Its’s a common medical mistake because the strategy actually has the opposite effect. The worse a disease gets, the harder and more expensive it is to treat!

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Going home—not so fast

Studies show that one in five patients return to the hospital within 30 days of discharge. Maybe because they were discharged before they were ready, not understanding discharge information or complications with their care. The transition from hospital to home may be anxious but it is also crucial and vulnerable.

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