Photo: Ron Levine

Almost any symptom can indicate something serious, but it doesn't mean it necessarily is. For example, back pain is benign 90 per cent of the time, but it can be life-threatening. Here, 10 symptoms you should not ignore.

1. Chest pain. Perhaps this is obvious but not to everyone. Don't chalk it up to heartburn. If it's a heart attack, you need to know that symptoms associated with cardiac chest pain include sweating, shortness of breath, dizziness and palpitations.

2. Shortness of breath. Don't decide it's just a cold or asthma, especially if you don't suffer from asthma. It could be your heart or your lungs. A blood clot in the lungs, a.k.a. a pulmonary embolus, can be deadly.

3. Sudden severe headache. Sometimes a headache is just a headache. But if you don't usually get headaches and you get a sudden one that is severe, get it checked out. It could be a bleed in your brain.

4. Rapid unexplained weight loss If you lose weight for no reason, i.e., you are not eating less or exercising more than you usually do, you need to find out why. It may be that you are not absorbing food properly or it may be a symptom of cancer.

5. Excessive urination When we drink a lot, we urinate a lot. That's normal, as the body keeps a balance of fluids. Urinating frequently, however, may indicate other things, such as infection (usually accompanied by burning on urination) or diabetes, especially if accompanied by unexplained excessive thirst.

6. Bleeding Normally we bleed when injured, and healthy blood makes clots to stop bleeding. If you are bleeding for no reason, however, it should be checked out. You may have a blood disorder. Blood in the stool or black, tarry stools, or vomiting blood means bleeding in the gastrointestinal tract. This can be caused by benign entities such as hemorrhoids, but can also be caused by cancer, and the bleeding can sometimes be severe. Blood in the urine needs to be checked. It can be caused by stones and infections, but also by cancer of the bladder or the kidneys. Coughing up blood may occur with infection (in small amounts) but more serious causes need to be ruled out, such as pulmonary emboli and cancer. Postmenopausal vaginal bleeding needs to be checked out to rule out a serious cause, such as cancer.

7. A swollen painful leg (without an injury) Leg swelling can result from injury, to be sure. But a single swollen painful leg is concerning for a problem with circulation, such as a blood clot. Swelling in both legs can result from a heart problem or something blocking the flow of blood back into the pelvis from the legs.

8. Severe abdominal pain Sometimes benign conditions, such as gastroenteritis, can cause severe abdominal pain. Some life-threatening conditions, however, can cause it as well, such as abdominal aortic aneurysm (swelling of the large blood vessel in the abdomen, potentially bleeding), ischemic colitis (lack of blood to the bowel, which can cause the bowel to die), appendicitis or cholecystitis (gallbladder inflammation, which often requires surgery to treat).

9. Severe back pain Most people experience back pain at some point in their lives, and the majority of back pain is musculoskeletal in nature (due to muscle strain, etc.), benign and resolves without any treatment. Severe back pain may be from kidney stones, which are usually benign, but you need to check them out. It may also represent serious infection or cancer. The red flags doctors use to indicate potentially serious back pain include duration of more than six weeks, age younger than 18 or older than 50, trauma, a history of cancer, night sweats, fever, chills, weight loss, night pain, IV drug use and neurological symptoms such as weakness and numbness in the legs or in the saddle area, or urinary retention
or incontinence.

10. Flashes of light Seeing flashes of light may indicate an oncoming migraine, but they may also be a symptom of retinal detachment, an eye emergency that needs emergency treatment.

Dr. Zachary Levine is an assistant professor in the faculty of medicine at McGill University Health Centre and medical correspondent for AM740 (a ZoomerMedia property).

A version of this article appeared in the June 2017 issue with the headline, "10 Reasons To Head to the ER—Stat!", p. 69-70.

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