How to tell if you have the flu

Published On: Jan 14 2014 09:41:41 PM EST   Updated On: Jan 15 2014 06:45:00 AM EST
JACKSONVILLE, Fla. -

This is the time of year for sharing -- viruses that is. Flu is peaking, but sometimes it's tough to pinpoint what is making you feel under the weather.

Dr. Susan Rehm says influenza has some very distinct characteristics, which can be treated.

"If you feel like you're getting symptoms of the flu you should contact your healthcare professional as soon as you can," she said. "You might be a candidate to take prescription anti-viral medication which specifically works against the flu."

Prescription anti-viral medications work best if they're started within the first 48 hours of getting the flu.  So, how do you know? Rehm says an easy way to tell if you have the flu is by spelling out the word "F-A-C-T-S".

The "F" stands for fever,  "A" for aches, "C" is for chills, "T" is for tiredness, and the "S" stands for sudden onset.

"Something that comes on suddenly, like you're being hit by a ton of bricks, may very well be flu," said Rehm.

Rehm adds  if you're vomiting, it's most likely not the flu, but some sort of stomach bug. She says colds are quantified by a stuffy nose, sore throat, and maybe hoarseness.

For more information on symptoms of the flu, go to flu.gov.