9 Signs It's More Serious Than the Common Cold

The common cold tends to clear up on its own in three to four days, says Melisa Lai Becker, MD, site chief of emergency medicine at Cambridge Health Alliance.

 It starts with a scratchy throat, congestion, and runny nose, and then a cough usually develops.

 While your cough and post-nasal drip may linger, most head cold symptoms should disappear after four days.

"With a cold, you ultimately feel OK after a couple days of rest, hydration, and Kleenex," she says.

If symptoms last for longer, it’s possible you have something more worrisome, such as the flu or mononucleosis.To be safe, make an appointment with your physician.