Dizziness, sweating and nausea may sound like the flu, but those symptoms also could be signs of a heart attack. And sometimes, a doctor will make the wrong call.

Each year, 5 percent of, or about 1 in 20, adults who seek outpatient care experience a diagnosis that is delayed, wrong or missed altogether, according to a conservative estimate in a September report by the Institute of Medicine (IOM). Although it seems like a small percentage, it adds up over time: The IOM estimates that most Americans will eventually experience a diagnostic error. These errors contribute to about 10 percent of patient deaths, according to the report.

Misdiagnosis can cause problems by missing the real issue and by causing patients to use unnecessary treatment.

“When you have a new diagnosis, doctors stop looking for what’s wrong with you and start treatment based on your supposed condition,” says radiologist and malpractice attorney Dr. Armand Leone, Jr. But if that diagnosis is wrong, you’ll get treatment you don’t need while your real problem goes undetected.

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Some diseases are more likely to be misdiagnosed, and knowing their signs and symptoms may be all it takes to get the right conversation going. Rare illnesses are more likely to be misdiagnosed, but doctors also can reach the wrong conclusions on conditions such as heart attacks, strokes and drug overdoses.

Here are common conditions that are often misdiagnosed, why it happens, and what you can do about it:

1. Heart attack

You might already know that chest and left-arm pain are common heart attack symptoms, but heart attacks don’t show up the same way in everyone. The pain during or before a heart attack can mimic chronic pain in the neck, shoulders or back. Other symptoms like dizziness, fatigue, nausea and cold sweats, may also mimic the flu.

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According to research published earlier this year in the journal Diagnosis, people who are younger or black are more likely to have a heart attack go undiagnosed. Heart attacks are rarer in young people, so doctors might not suspect one in those cases. Black people have a higher incidence of heart attack in general, but they often do not show evidence of disease on tests such as angiograms, which can lead to incorrect diagnoses.

2. Certain cancers

Delayed diagnosis errors are common in cancer, specifically lung, breast and colorectal cancers. Those types of cancer accounted for about 10 percent of physician-reported errors in a study published in the Journal of the American Medical Association.All other cancers combined accounted for nearly 10 percent of all 583 diagnostic errors reported in the study.

Doctors in the study were most likely to report that the diagnosis was delayed because they’d neglected to get a biopsy after an abnormal test result.

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3. Pulmonary embolism

Another vascular disease, pulmonary embolism, occurs when a blood clot forms in or reaches the lungs through the bloodstream. It was one of the most commonly missed diagnoses in the JAMA study of self-reported physician errors, accounting for 4.5 percent of all diagnosis errors.

The symptoms of pulmonary embolism are very similar to a chest cold, asthma or pneumonia: chest pain, coughing and wheezing. Additionally, several tests must be performed before a doctor can confirm pulmonary embolism, so when doctors aren’t thorough, or there’s just one false negative, pulmonary embolisms are often missed.

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4. Drug intoxication or overdose

A missed diagnosis of intoxication was self-reported in 4.5 percent of error cases in the JAMA study, similar to pulmonary embolism. Part of the problem is that patients may not always be forthcoming with their use of illegal substances.

All too often, however, the intoxication or overdose is from drugs prescribed by a doctor, usually opioid painkillers. Patients using these drugs— such as OxyContin, Vicodin, and Percocet— tend to be older and have chronic conditions, so doctors may not think of an overdose first when searching for a diagnosis.

Opioid painkiller prescriptions have risen sharply since 1991, and deaths from overdose have more than quadrupled since 1999, according to the National Institute of Health (NIH).

5. Stroke

A stroke diagnosis, like that of cancer, is also likely to come late, about 9 percent of the time, according to one study published in the British Medical Journal.

Symptoms of a stroke include weakness, confusion, poor coordination and difficulty speaking. Most often, strokes occur suddenly, with all symptoms appearing within minutes. However, some people experience a much slower onset, with symptoms exhibiting over hours or days, and these patients are more likely to be misdiagnosed. In addition, some physicians initially mistake strokes for migraines.

What you can do

It might seem like the diagnosis is all in your doctor’s hands, but you can help make sure she gets it right. To avoid misdiagnosis, or to get to the right diagnosis faster, follow these tips:

● Keep track of your symptoms, when they happen, and how severe they are.

● Always tell your doctor the truth about what substances you’re using, from cigarettes to painkillers.

● Ask your doctor to follow up on abnormal test results.

● Ask how long it should take for your medication to work, and follow up if it doesn’t.

● When in doubt, always get a second opinion.

● Remember, you know your body better than anyone. If something doesn’t feel right, keep asking questions.