Is it a cold or a sinus infection? How to differentiate the common cold from a more serious sinus infection

• Having a cold can increase your risk of developing a sinus infection.
• Symptoms of a sinus infection can last up to ten days and often get worse with time.
• If you have a cold, you'll usually start feeling better within three days.

You're miserable, with a stuffy nose, a cough, and a sore throat. But is it a sinus infection or a cold? It can be difficult to tell since the symptoms of these two conditions are largely the same.

"If you're having trouble telling the difference between sinusitis and a cold, you are in good company. Doctors struggle with this distinction as well," says Jim Keany, MD, an emergency room physician and former chief of staff at Mission Hospital in Orange County, California.

Having a cold can increase your risk of developing a sinus infection because the congestion in your nose can keep the sinuses from draining as they normally would, says Chris Thompson, MD, an Ear, Nose and Throat specialist and otolaryngologist with Head and Neck Associates in Mission Viejo, California.

The only way to know for sure whether you have a cold or a sinus infection is for a doctor to send some of the fluid draining from your sinuses to be cultured in a lab, says Keany, but that's rarely done. Instead, doctors use a combination of your symptom history, risk factors, and physical exam to make a diagnosis.

Here's what you should know about colds and sinus infections, and when to seek medical advice.

What is a sinus infection?

A sinus infection, also known as sinusitis, occurs when fluid fills the sinuses — pockets in the face that are normally filled with air. Once these pockets are filled with fluid, viruses, or bacteria can take hold, causing a sinus infection.

Anything that can cause the sinuses to become blocked — including a cold or allergies — can increase your likelihood of developing a sinus infection, Thompson says. People who have physical conditions that can block the sinuses, like nasal polyps, are also at increased risk.

Common symptoms of a sinus infection include:

• A runny or stuffy nose
• Dry cough
• Pain or pressure in the face
• Headache
• Post nasal drip
• Bad breath

Symptoms of a sinus infection can last up to ten days and often get worse with time. Your doctor may recommend antibiotics, but sinus infections can resolve on their own, Thompson says. If your symptoms last longer than a week, your facial pressure is particularly painful, or you have a fever, it's time to see a doctor, he says.

Since there's no quick fix for sinus infections, many treatments focus on controlling the symptoms and making the patient more comfortable. These remedies can help:

• Use a nasal decongestant or allergy medication to control additional mucus.
• Use saline irrigation, like a neti pot, to clear fluid from the sinuses.
• Breath in steam, like from a hot shower, to help loosen mucus.
• Use a warm compress on the face and nose to alleviate pressure.

In rare cases, some people suffer from chronic sinus infections. If your symptoms last longer than 12 weeks or you've been treated for three or more sinus infections in a year, see an otolaryngologist, Thompson says.

What is the common cold?

The common cold is caused by a virus that will often trigger symptoms like congestion and excess mucus production. Although there are more than 200 viruses that can cause a common cold, rhinoviruses are the most common and cause about 30% of colds, Thompson says.

Common symptoms of a cold include:

• Sneezing
• Stuffy or runny nose
• Coughing
• Sore Throat
• Post nasal drip
• Watery eyes

Cold symptoms can last up to 14 days, but they usually peak by day 3 and begin getting better from there. If you have symptoms that are still getting worse after 10 days, have difficulty breathing, or have a fever for more than 4 days you should see a doctor.

There's no cure for a cold, and it will resolve on its own. However, there are steps you can take to feel better, including:

• Rest.
• Stay adequately hydrated.
• Use steam to loosen mucus.
• Use a cool mist humidifier.
• Try honey to alleviate cough (shouldn't be given to children under 1).
• Talk to your doctor about over-the-counter medications that might help with symptoms.

Similarities and differences

Although it's hard to tell colds and sinus infections apart, there are some differences. Thompson says the best way to distinguish between the two conditions is to monitor the duration of symptoms.

"Colds usually improve significantly after a week, whereas a sinus infection worsens after five to seven days or lasts longer than 7-10 days," he says.

Generally speaking, colds are less serious than sinus infections, although neither is fun to have.

"Both contribute to patients' suffering," Thompson says. "Many times, colds have less severe symptoms. Bacterial sinus infections, if left untreated, can result in severe infections spreading to the eye, brain, or forehead. This often requires hospitalization, surgery, and IV antibiotics [in extreme and rare cases]."

While colds can resolve on their own, sinus infections often need antibiotic treatment. However, remember that a cold can cause a sinus infection, so it's important to keep an eye on your symptoms.

Insider's takeaway

Colds and sinus infections can both make you miserable. However, if you have a cold you'll usually start feeling better within three days, while a sinus infection will start getting worse at that point.

Many of the home remedies — like over-the-counter decongestants, breathing steam, and using saline irrigation — are the same for both sinus infections and colds. A cold doesn't need a dedicated treatment to go away, while a sinus infection might require antibiotics.

"The common cold is viral, which resolves naturally due to the normal function of your immune system," Keany says. Sinus infections, on the other hand, are often bacterial and the infection can spread if you don't treat them with antibiotics, he says.

If you're still feeling sick after a week, it's time to see a doctor.

Related articles from Health Reference:

• Is pneumonia contagious? Yes, when it's caused by bacteria or viruses
• You're most contagious with the cold virus in the first three days of infection
• You can't sweat out a cold, and trying to could make it harder for you to recover
• To get over a cold fast, eat foods rich in vitamins and minerals like vitamin C, zinc, magnesium, and calcium
• When it's OK to work out with a cold and when you should stay in bed