Signs vs. Symptoms: What's the Difference?

You Can Feel Symptoms and Show Signs of a Health Problem

man with thermometer
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You've probably seen the label "Signs and Symptoms" while researching medical conditions online. Since most people understand the idea of indications and feelings related to health problems, why is it necessary to say signs and symptoms? Aren't they the same thing?

It's true that the two words are synonyms and that they refer to evidence that something's not quite right with your body. Yet, medically speaking there is a difference between them.

 Signs are visible externally and symptoms are internal feelings.

Signs vs. Symptoms

Symptoms can only be described by the person feeling them. If you are having pain, no one knows unless you tell them. It's the same with dizziness, numbness, lightheadedness, fatigue, vision disturbances, ringing in your ears, and a whole host of other feelings. Anyone who is not in your body is only going to know about these experiences if you describe them.

That doesn't mean other people don't notice when you are not feeling well. If your face is pale, you are unstable when you walk, or you are sweating, then you are showing signs. Signs have to be seen and read by someone (e.g., a family member or healthcare provider) rather than felt. Signs are just what they sound like: indicators of a problem.

Types of Medical Signs

The most important signs of all are called the vital signs. Vital signs include your breathing rate, heart rate (pulse), temperature, and blood pressure.

Vital signs also can include other measurements, such as pulse oximetry (how much oxygen is in your blood).

People read signs all the time. Need to go to the 4th floor? Push the elevator button next to the sign with the "4" on it. Need to take the freeway north? Read the signs to find the correct on-ramp.

Medical signs aren't always read with the eyes. Sometimes we read signs by touch or by listening. Some of the most common signs we assess in the medical field are the skin signs: color, temperature, and moisture. People who are pale, cool, and moist are usually feeling pretty bad.

Parents read signs from the day they bring their first child home. The baby's crying may be a sign she needs to be fed.

Simultaneous Signs and Symptoms

Sometimes, signs indicate symptoms—like how a crying baby may be a hungry baby. Is your daughter scratching her arm (sign)? She must feel itchy (symptom). People vomit (sign) when they are feeling nauseated (symptom).

Most medical conditions have both signs and symptoms that help identify what is wrong. 

For example, heart attack patients will often complain of symptoms like pain or pressure in the chest and arm. They may also show signs like clutching the arm or chest, a pale face, sweating, abnormal heart rate, and high blood pressure. No matter which signs or symptoms they're experiencing or exhibiting, the matter is just as serious.

Reading About Signs and Symptoms

Quite often, people who write about medicine and health will interchange the two words. Some prefer to keep it simple and use "symptom" more often because it's a clear indicator of what they're explaining.

There are also times when a reader can overlook the word "sign" but will pay attention to "symptom." 

While there is a technical difference between the two words in a medical sense, what's more important is the information surrounding them. As you're reading up on any medical condition or talking with your healthcare team, pay attention to both signs and symptoms. In the context of your health, particularly in an emergency, semantics should be the least of your worries.

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