9 Symptoms You Should Never Ignore

6. Shortness of Breath

The big worries: Sudden shortness of breath can indicate a pulmonary embolism — when a blood clot forms in the body's deep veins (usually in the legs), travels to the lungs and gets lodged in the lung's blood vessels. Suspect an embolism if you've recently traveled, have undergone surgery or have been immobile, and/or your shortness of breath is accompanied by chest pain and coughing up blood. If you find yourself gasping after climbing two or three stairs or getting tired sooner than you used to, doctors will want to rule out chronic obstructive pulmonary disease (COPD), especially if it's accompanied by a cough and fatigue and you have a history of smoking. Irregular heart rhythm, congestive heart failure and other types of heart disease are additional possibilities. When organs aren't getting enough oxygen, breathlessness can result. See a doctor — stat.

What else it might be: Shortness of breath can occur with asthma, bronchitis or pneumonia. You can also experience shortness of breath, sometimes with heart palpitations, if you are under extreme emotional distress or anxiety. Regardless, patients should go to the doctor. "I don't jump to a psychological issue unless there is nothing else going on," says Factora. "But we don't want to miss those few cases where survival is at stake."

7. Sudden Confusion

The big worries: If you're experiencing sudden confusion, personality changes, aggression or an inability to concentrate, it's important to see a doctor right away. "The mortality rate for severe confusion is pretty high. You have to figure out what's going on," says Bronson. In the worst case, a brain tumor or bleeding in the brain could be behind the delirium. If you're also experiencing slurred speech, difficulty finding the right words, or numbness or weakness in the face, hand or leg, stroke is a strong possibility. "You have a window of about two to three hours to get to the hospital," says Cedars-Sinai's Black. Beyond that, brain loss may be irreversible.

What else it might be: Medicines and drug-alcohol interactions can also affect your mental state. Plus, confusion can signal an infection, abnormal blood pressure, low blood sugar or dehydration, each of which should be ruled out by a physician.

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