Health Conditions That Are Commonly Misdiagnosed

Pick any episode of any hospital drama (current or syndicated), and there's an excellent chance the plotline will involve a misdiagnosis. No, really, think about it. A common scenario on these shows is a patient diagnosed incorrectly and given the wrong treatment, creating drama as their condition worsens. And while this can make for must see TV, in real life, misdiagnoses could be dangerous.

Around 12 million people in the United States are impacted by being misdiagnosed. In fact, every year anywhere from 40,000 to 80,000 individuals don't survive their misdiagnosis (via the Society to Improve Diagnosis in Medicine). And roughly six million of those individuals might experience harm because they received the wrong diagnosis, according to BMJ Quality & Safety. Frightening statistics to be sure, but you're not helpless.

Yes, it takes a great deal of education and training to be a doctor. And, yes, Googling symptoms and self-diagnosing yourself and others can be dangerous. But educating yourself about the possible causes behind your symptoms means you'll have an easier time asking questions at medical appointments and understanding what your healthcare professional tells you about your condition. Keep in mind that the human body is complex, and the following are only a few of the possible misdiagnoses that can occur.


Your appendix is a tube attached to your large intestine. The University of Washington (UW) explains that the appendix is very small, so it can become blocked, which could lead to infection. This can cause inflammation, a condition known as appendicitis. And when this occurs, it might be necessary to remove the appendix. However, it's not uncommon for a patient to have their appendix removed unnecessarily due to their condition being misdiagnosed as appendicitis.

According to the UW, appendicitis usually causes pain. Specifically, you might feel discomfort on the lower right side of your torso. But this pain could also be symptomatic of a different type of infection. A woman could be diagnosed with appendicitis when she actually has an infection in her uterus or ovaries. She also might be experiencing a type of pregnancy (ectopic) where a fertilized egg attaches to the outside of her uterus. A man, on the other hand, might experience pain similar to an inflamed appendix when he really has an intestinal tract infection. He also might have inflammation in a lymph node.

So, can you live without your appendix? Yes, but as surgeon Dr. David Flum explains on UW's website, "Removal of a normal appendix is not trivial by either cost to society, or cost to the patient individually." And, yet, he also said a surgeon is likely to remove an appendix even if they only suspect the patient might have appendicitis to avoid possible complications.

Sleep apnea

Do you have difficulty focusing? Do you often forget things and are constantly disorganized? And what about your mood — are you often irritable? Well, according to Bogrow & Associates, you might have sleep apnea ... or attention deficit hyperactivity disorder (ADHD).

Okay, let's take this one step at a time. Sleep apnea is when something blocks your breathing while you're asleep, which can interfere with you getting a good night's rest (via Bogrow & Associates). ADHD is a developmental disorder. And, yes, ADHD can involve similar symptoms as sleep apnea, like easily becoming distracted and having a shortened attention span — but it also can make you more likely to fidget and need to constantly move around, explains Bogrow & Associates. 

Despite not all of the symptoms being the same, it's very common for someone with sleep apnea to be misdiagnosed as having ADHD. In fact, the initial symptoms of both of these health issues can be very similar, and it can take some time to discover a misdiagnosis has taken place. Case in point, Bogrow & Associates describes a male patient misdiagnosed as having ADHD. He went on medication for months before learning that he actually had sleep apnea. Fortunately, a sleep study helped the patient get to the bottom of his symptoms. 

Take note: If you have any of the above symptoms, you might want to contact a sleep specialist.

Lyme disease

If you're bitten by a tick carrying certain bacterium, you could contract Lyme disease, according to the Centers for Disease Control and Prevention (CDC). But this health problem can be harder to diagnose than you might expect. It's possible for a medical test to show you have Lyme disease when you actually have a different type of bacterial infection, according to the University of Michigan Health (UMHS). Or you might not have Lyme disease, but a test gives you a false positive because you had Lyme disease in the past. Also the reverse could happen — a test comes up negative for Lyme disease when you actually have it. And this is only the tip of the iceberg when it comes to misdiagnosing Lyme disease.

For example, Lyme disease can make your joints and muscles hurt, according to the CDC. But this can also be a symptom of arthritis, including rheumatoid arthritis, which involves your immune system mistakenly treating your joints as if they were dangerous foreign invaders, according to the Mayo Clinic. Another type of arthritis that can have similar symptoms to Lyme disease is juvenile idiopathic arthritis, notes the UMHS. And as its name indicates, it's a form of arthritis that affects children.

Besides arthritis, Lyme disease and fibromyalgia can also have similar symptoms (via the UMHS). For example, fibromyalgia can cause pain, according to the Mayo Clinic, but it tends to be more widespread. Plus, both Lyme disease and fibromyalgia can bring on fatigue.

Celiac disease

Chances are you've seen the word "gluten" — or even more specific, "gluten free." This type of protein, which is in products made from rye, barley, and wheat, can be problematic for someone who has celiac disease, according to the University of Chicago Medicine. However, this autoimmune disease is sometimes mistaken for a different gluten-related disease.

As the University of Chicago Medicine explains, celiac disease can greatly differ from case to case, which can make it harder to properly diagnose. For example, both celiac disease and non-celiac gluten sensitivity (NCGS) can cause exhaustion, pain in your abdomen, and bloating. And yet, a person with celiac disease cannot have any gluten while a person with NCGS can usually consume some without severe consequences. So, a person being misdiagnosed with NCGS when they really have celiac disease could do more damage to their body.

Besides NCGS, celiac disease might also be confused for an allergy to gluten since both can involve pain in the abdomen, notes the University of Chicago Medicine. However, a gluten allergy can be fatal and might include other symptoms like breathing issues, swollen tongue and/or lips, and hives. In addition, gastrointestinal doctors usually treat celiac disease, while allergists (and dietitians) treat patients with a gluten allergy. So, if you are diagnosed with one of these health issues and would like a second opinion, you might want to visit a different type of medical professional.


Lupus is a chronic disease where your immune system attacks your body, causing inflammation, according to the Lupus Foundation of America. As you can imagine, immediate diagnosis and treatment can be crucial to properly manage this health problem. Unfortunately, studies have found that some people with lupus aren't properly diagnosed for as much as six years after they first start noticing symptoms (via Lupus Foundation of America).

Remember, lupus can cause pain in the joints, which is also a symptom of rheumatoid arthritis, according to AARP. Someone with lupus can also experience exhaustion, but so can a person with chronic fatigue syndrome. And as we discuss elsewhere in this article, fibromyalgia can also cause pain and fatigue, according to the Mayo Clinic. In fact, AARP notes that lupus sometimes "mimics" fibromyalgia, making it possible for one to be mistaken for the other.

Although the idea of lupus being diagnosed incorrectly is a very grim thought, the Lupus Foundation of America conducted a study to help improve the misdiagnosis rate of lupus. While the data they collected from more than 3,000 individuals with lupus was not encouraging (more than 50% of them were told that they had no ailment), it did dive into the diagnostic experience of patients on a new level. "The results of this study will help us understand and in-turn, prevent the specific factors that lead to unacceptable delays in receiving a lupus diagnosis," says R. Paola Daly, director of research at the Lupus Foundation of America.

Chronic fatigue syndrome

Imagine constantly feeling exhausted. You try to go about your day, but whether it's working on the computer or walking on the treadmill at the gym, you only feel worse. Even sleep (if you can sleep) doesn't seem to help. This could be a condition called chronic fatigue syndrome or CFS, according to MedicineNet. However, this level of fatigue can also be a symptom of a number of other health issues.

For example, chronic mononucleosis can also cause similar symptoms as CFS, especially since CFS can vary from person to person, according to MedicineNet. And, yes, mononucleosis or mono is called "the kissing disease" for a reason, according to MedicineNet. Infectious mononucleosis can be spread via saliva. However, you can also catch it by drinking from the same glass as another person or using their toothbrush. In addition, CFS can share symptoms with health concerns like narcolepsy, schizophrenia, and even cancer. And besides conditions and ailments, sensitivities to certain chemicals, including medications, could also bring on a reaction that mimics CFS.

So, are there any red flags of CFS? Noting your exact symptoms when you speak with a healthcare professional can help with your diagnosis, according to MedicineNet. For example, short-term memory issues can be a sign of CFS. Also, keep track of how long you've been experiencing these symptoms. If it's been at least six months, and other ailments are ruled out as the cause, then it's possible you have CFS.


As Psychology Today points out, it's not easy to test for mental illnesses. While there's devices like MRIs, X-rays, and sonograms that can help discover other health concerns, conditions like depression usually rely on what a patient conveys (or doesn't convey) to their healthcare professional, along with a checklist of symptoms. So, it's no wonder that depression is sometimes mistaken for a different mental illness.

For example, both depression and bipolar disorder can result in someone experiencing intense negative emotions, including having suicidal thoughts and tendencies, according to Psychology Today. However, bipolar disorder can also involve extreme emotional highs (referred to as mania) where someone can feel confident and euphoric. Okay, but wouldn't those moments of mania be a red flag that someone isn't experiencing depression? Not necessarily if the patient tells a healthcare professional only about their negative emotions and not their mania. In fact, bipolar-related mania can make you feel more productive, so it's possible a patient might not even think of it as a symptom of anything.

Besides bipolar disorder, depression can also be mistaken for an underactive thyroid (hypothyroidism) since both conditions can have similar symptoms like exhaustion and feeling low, explains Psychology Today. In addition, type 2 diabetes is another condition that has similar signs of depression (exhaustion, inexplicable weight loss, and irritability), meaning a person could be diagnosed with a mental illness when what they really have are issues with how their body uses insulin.

Aortic dissection

Known for his work on shows like "Three's Company" and "8 Simple Rules for Dating My Teenage Daughter," actor John Ritter passed away in 2003 from an aortic dissection. This condition is when the aorta blood vessel, which moves blood away from the heart, tears on the inside and can eventually cause the blood vessel to split open, according to WebMD. But following his death, his widow brought a lawsuit against a hospital that allegedly had misdiagnosed him on more than one occasion, according to CNN. Eventually, this lawsuit was settled. The specifics of Ritter's case aside, aortic dissection can be mistaken for other conditions related to the heart.

Most people who have an aortic dissection are likely to experience intense pain specifically on their upper back between their shoulders, explains WebMD. You might have pain in your arms, neck, and less often your chest. But despite chest pain not usually being a symptom, it can be hard to tell the difference between an aortic dissection and a heart attack. In fact, an aortic dissection can lead to a heart attack even though the two are different conditions that can both be fatal.

Besides intense pain, symptoms of aortic dissection can include the legs feeling numb to the point that you can't move them, according to WebMD. You also can lose your pulse and go into shock. So, if you or someone else is experiencing any of these symptoms, contact emergency services.

Irritable bowel syndrome

It's time to get a little personal. Diarrhea and constipation are about as opposite as two health problems can be. And yet both of these conditions can be symptoms of irritable bowel syndrome or IBS, according to WebMD. This is because IBS affects both the intestines (including the part of the large intestine that is the colon), which is why cramping, bloating, and gas can also be IBS-related issues. However, as WebMD points out, all of these symptoms can make it difficult to properly diagnose a case of IBS.

For example, stress can interfere with how your body processes food and cause similar symptoms as IBS. This, in turn, can lead to more stress, which might only exacerbate your symptoms. Additionally, IBS could be confused for diverticulitis where pockets form in your colon, tear, and become infected and inflamed. And IBS can be mistaken for lactose intolerance where your body cannot properly break down lactose, which is sugar in foods like cow's milk.

Besides these conditions, IBS and stomach cancer also share certain symptoms like bloating and discomfort in the belly area, according to WebMD. Obviously, misdiagnosing one for the other can have serious consequences, so don't be afraid to seek a second opinion. Remember, red flags of stomach cancer can include vomiting, heartburn, inexplicable weight loss, and stool that contains blood. However, don't try to self-diagnose yourself or someone else. Instead, let a medical professional know about all of the symptoms.

Parkinson's disease

Although certain symptoms are usually associated with the neurodegenerative disorder known as Parkinson's disease, how these symptoms develop and progress can vary from person to person, according to the Parkinson's Foundation. And some of the most common health issues connected to this disease can also be symptoms of other conditions (via the Parkinson's Foundation).

For instance, someone with Parkinson's could experience tremors in their hands. However, so can someone with essential tremor, which is believed to be a different health concern from Parkinson's despite their similar symptoms (via EPDA). A person with Parkinson's could also have difficulty maintaining balance, but so too can someone with Normal Pressure Hydrocephalus where the body has difficulty properly draining fluid from the brain. And dementia with Lewy bodies where a type of protein accumulates on one's brain and can lead to rigidity and slower muscle movements — both of which are also common symptoms of Parkinson's (via the Parkinson's Foundation).

Beyond these conditions, Parkinson's can also cause your face to appear different, which means it could be confused for a stroke, according to WebMD. Stiffness in your neck can also occur with Parkinson's, but if you combine that with difficulty balancing, facial changes, and trembling in your arms, then it's possible to mistake a Parkinson's episode for stress, Alzheimer's disease, or a head injury. All the more reason to seek medical assistance if you or someone else experiences any of these symptoms. And, of course, don't be afraid to seek a second opinion.

Multiple sclerosis

Did you know your nerves have a protective casing? However, if someone has multiple sclerosis (MS), then their body's immune system goes after that casing the way it normally would a dangerous virus, according to the Cleveland Clinic. And as Dr. Jeffrey Cohen, director of experimental therapeutics at the Mellen MS Center, told Everyday Health, there's no one single test for determining if someone has MS. So, misdiagnoses do happen regularly for this condition.

Case in point, a study in the journal Neurologia concluded that migraines and depression can be connected, as cited by Everyday Health. However, depression can also be a symptom of MS, leaving the door open to migraines and MS being mistaken for one another. And data from a different study published in the journal Clinical Neurology and Neurosurgery found that migraines can happen as a result of MS. But remember, that doesn't mean a person without MS cannot get a migraine. And besides migraines, spondylopathies, which is an umbrella term for different disorders involving the backbone, can cause exhaustion and discomfort in the joints — both of which can also be symptoms of MS.

While similar symptoms can lead to a misdiagnosis for health issues, MS can also be mistaken for radiologically isolated syndrome even though they don't usually share symptoms, according to Everyday Health. This is because both radiologically isolated syndrome and MS can cause abrasions on one's brain, which can be seen via an MRI.

Panic disorders

Undoubtedly, people have been having panic disorders for millennia, but the idea of a panic disorder being a condition didn't occur until 1980, according to Vista Pines Health. Because of this, there isn't a universal consensus in the medical community as to what exactly are the aspects of a panic disorder. And that can lead to misdiagnoses.

To fully understand how an incorrect diagnosis can happen, it's important to remember that panic disorders are classified by Diagnostic & Statistical Manual of Mental Disorders as a type of anxiety disorder, as cited by Vista Pines Health. This means they can have similar symptoms to other types of anxiety disorders. For example, obsessive-compulsive disorder (OCD) can be confused for panic disorders. And if you think about it, it makes sense. Panic disorders involve feeling terrified for no apparent reason, according to MedlinePlus. OCD can involve obsessing over fears to the point that repeated compulsive actions become a coping mechanism, according to the Cleveland Clinic. With that in mind, it's also possible to misdiagnose panic disorders for other anxiety disorders like post-traumatic stress disorder and social anxiety disorder.

While panic disorders being mistaken for other anxiety disorders might not be surprising, it's not the only way it can be misdiagnosed — or rather overlooked during a diagnosis. As Vista Pines Health explains, a person can have both depression and panic disorders. However, it's possible the symptoms of one may overshadow the other, giving the patient an incomplete picture of their mental health.

Cluster headaches

Here's the good news. As Dr. Juline Bryson, assistant professor of neurology at Wake Forest Baptist Medical Center, told WebMD, cluster headaches are not common and can be easily treated and prevented with medication. But there is a catch. Because these headaches are rare, they also tend to be misdiagnosed.

According to Dr. Bryson allergies are sometimes mistaken for cluster headaches. Remember, even though there are different types of allergic reactions (sneezing, watery eyes, etc.), one of them is headaches. Additionally, Dr. Bryson says migraines and cluster headaches are sometimes misdiagnosed for one another. But there are some important clues that can help you tell them apart. As the Mayo Clinic points out, migraines can last for days, fluctuating in severity during that time but never fully going away. Cluster headaches, on the other hand, could last for only half an hour, although you might experience more than one cluster headache in a single day.

While it can be difficult to tell a cluster headache from other types of headaches, there are a few symptoms to watch out for if you suspect you're experiencing cluster headaches. Typically, they only affect one side of your head, which might appear red, according to WebMD. The pain usually occurs after waking up and might be accompanied by sweating and congestion.

Pulmonary embolism

This next condition is not only possibly life-threatening but also often misdiagnosed, according to the Cleveland Clinic. Remember that the circulatory system connects to all the parts of your body, including the lungs. It does this in part through its arteries. But pulmonary embolism is when something blocks the arteries connected to the lungs (a clot, for example). And, unfortunately, it's sometimes confused for other health problems.

As Dr. Richard Krasuski, director of adult congenital heart disease services at the Cleveland Clinic, explains, the size of the blockage can make a difference when it comes to properly diagnosing pulmonary embolism. For example, you can also experience pain during a heart attack, but that same level of pain could be a red flag of pulmonary embolism, notes Everyday Health. And yet, pain doesn't always accompany this type of embolism because large clots blocking the arteries to the lungs usually don't cause pain.

Besides possibly being confused for a heart attack, pulmonary embolism can also cause breathing issues, which can lead to being misdiagnosed as pneumonia, according to Everyday Health. However, there are some symptoms to watch out for if you think you're experiencing pulmonary embolism, like a fast heartbeat, says the Cleveland Clinic. Also, ask yourself if you're experiencing chest pain, and if anything makes that pain worse. In particular, does coughing or taking a deep breath seem to worsen your pain? But even if you just suspect you have pulmonary embolism, seek medical help right away.