Do you think your doctor has made a misdiagnosis? It is more than possible. Studies show that over 20% of patients are misdiagnosed, according to the AARP. Doctors make mistakes but when it comes to serious medical conditions, getting the right treatment is essential.

To protect yourself against being misdiagnosed, carefully taking note of your symptoms is a good start, in addition to being aware of the diseases that are commonly misdiagnosed by doctors, as was recently highlighted in a report by the health news outlet Eat This, Not That! Here are nine conditions commonly misdiagnosed by doctors:

1. Fibromyalgia. This disorder shares the same symptoms as certain rheumatic diseases such as lupus and rheumatoid arthritis, which is why it is so easily misdiagnosed. Fatigue, aching muscles, joint pain, and mood issues are all characteristics of fibromyalgia, but it is easy for doctors to overlook this illness.
2. Celiac disease. Roughly 83% of people have either been misdiagnosed or undiagnosed with celiac, an autoimmune condition in which the body reacts to gluten by attacking the intestines. Dr. Sophie Balzora, a gastroenterologist at NYU Langone, explained that a blood test for certain antibodies is the best way to rule out celiac disease.
3. Cancer. It is scary to think that over 40% of the time, doctors misdiagnose certain types of cancer. It is, however, understandable. Symptoms can be hard to pin down and could indicate other health issues.This is why a second opinion is so important, especially if your doctor does not specialize in cancer.
4. Depression. Depression can manifest physically in the body and bring symptoms including headaches, fatigue, body aches, and muscle pain. Doctors tend to focus on, and treat, these physical symptoms, but they don't always find out about their patients' moods and mental state, which is why depression is often misdiagnosed.
5. Parkinson's disease. Symptoms begin gradually with Parkinson's disease. A slight hand tremor, some unsteadiness, perhaps some stiffness — these all mimic other conditions that affect the nervous system. Seeing a neurologist for a second or even third opinion could save you from bouncing back and forth seeking a diagnosis.
6. Aortic dissection. Often, medical professionals misdiagnose this serious heart condition as a heart attack. Getting quick treatment is essential for aortic dissection, which can be diagnosed via a CT scan or X-ray.
7. Thyroid conditions. Essential bodily functions are governed by the hormones released by the thyroid. An underactive thyroid can cause symptoms like fatigue and weight gain, while an overactive thyroid could cause rapid heartbeats and weight loss. A blood test that checks the TSH hormone levels will help diagnose any thyroid conditions, which can be treated with medication.
8. Migraines. Headaches can accompany various health issues that range from depression to sinusitis, so a person experiencing migraines may be misdiagnosed as having one of those conditions instead. The good news is that a neurologist can diagnose migraines by conducting a neurological exam.
9. Multiple sclerosis. Diagnosing this autoimmune disease is tricky. Patients could spend years in treatment for other conditions like nerve damage or migraines. "Both the symptoms and MRI testing results can look like other conditions, such as stroke, migraines and vitamin B12 deficiency," explained Dr. Marwa Kaisey, from Cedars-Sinai Medical Center in Los Angeles.

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