Everyone knows what a cold is like—congestion, sneezing, coughing, and all the rest. But when is a “cold” not just a cold?
A cold is sometimes mistaken for a sinus infection. They share some symptoms, and thus many people with sinus infections chalk it up to a particularly nasty cold and don’t seek treatment.
What is a cold?
A cold happens when a virus infects the upper respiratory tract, which consists of your nose, mouth, throat, and lungs. There are many different viruses that can cause such an infection. A few days after the virus sets in, you may experience cold symptoms, which include cough, sore throat, sneezing, and stuffy nose. The exact biological mechanism by which these symptoms appear still isn’t clear to medical professionals, despite the fact that the cold is such a common illness.
Your body defends itself automatically against the virus, and this immune response usually clears up the symptoms within a week or 10 days.
Adults often get up to four colds per year, and colds spread from person to person very easily. There is no cure, but the symptoms may be eased with the use of over-the-counter medicine, such as decongestants to help clear a stuffy nose. Talk to your doctor to determine the appropriate treatment for your symptoms.
What is a sinus infection?
Colds can cause sinus infections, but not all sinus infections are caused by colds. Sinus infection symptoms can sometimes be caused by bacterial infections.
The sinuses are air-filled cavities in the face, behind the nose, and in the cheeks. These cavities are lined with mucosa, which is a type of tissue that generates a protective, lubricating fluid called mucus. Normally, the sinuses are coated with a thin layer of mucus, which traps tiny particles and bacteria and keeps them from getting further inside the body.
The sinus walls also have a layer of little hairs called cilia, which sweep the mucus—and whatever’s caught in it—down toward the back of the throat, where you swallow it. From there, your body digests and disposes of the matter that’s been filtered out. This is an automatic process that you normally don’t even think about, like breathing.
When your mucus membranes get infected, or when you have allergic reactions, they swell up. This blocks the cilia from doing their continuous sweeping job. It also traps mucus in the sinuses.
Sinus infections are often accompanied by cloudy or colored drainage from the nose, either dripping from the nostrils or draining into the throat, along with:
- nasal obstruction, congestion, blockage, or stuffiness
- a feeling of pain, pressure, or fullness in the front of the face or around the eyes
- or both of the above
The “cloudy or colored” mucus is called “purulent” by doctors. A cold, which does not necessarily trigger sinus infections, usually produces clear mucus. Purulent discharge may indicate that you’re dealing with something more than a run-of-the-mill cold.
Particularly when the infection is ongoing or keeps coming back, figuring out the cause can help a physician or an Ear, Nose, and Throat (ENT) specialist choose the most effective treatment—what works against allergies may not be effective against bacteria, for example.
I have symptoms. What can I do?
Colds typically clear up on their own, and so do some sinus infections. Antibiotics—which must always be prescribed by a doctor—aren’t effective against colds, but may be effective against bacterial sinus infections. If symptoms do not clear up within 7 to 10 days, or if the discomfort is particularly severe, a doctor is the appropriate person to advise you on the next course of action.
Talk with your doctor for more information.