Your head aches. You’re stuffed up. Is it cold? Or a sinus infection? Here’s how you can tell the difference–and why it matters. What Colds and Sinus Infections Have in Common Colds and sinus infections both affect the upper respiratory system and make us feel generally lousy. Both include nasal congestion, and both can be associated with a cough and aching head. Both are also incredibly common: you’d be hard-pressed to find an adult human being who hasn’t had both a cold and a sinus infection. Most sinus infections and all colds are caused by viruses. A sinus infection can also be caused by bacteria. In fact, people often develop what’s called a secondary sinus infection—essentially, a sinus infection that occurs as a result of a cold. How it happens: when you have a cold, the membranes lining your nasal passageways swell up and produce excess mucus. This swelling can cause the mucus to become trapped in your sinuses. Bacteria love warm, dark, moist places, such as stuffed-up sinuses, and can grow and thrive in the sinus, triggering a sinus infection. Most colds do not turn into sinus infections. In fact, according to the American Academy of Family Physicians, only about two out of 100 people with cold symptoms will develop a bacterial sinus infection. The Common Cold Common colds are rarely serious. They usually come and go without causing too much pain, discomfort or distress. The hallmarks of a common cold include: Clear, thin nasal drainage: It’s completely normal to be stuffed up when you have a cold. Usually, nasal mucus is relatively thin and clear at the beginning of a cold. It may get thicker and become whitish, yellowish or green as your cold progresses, but then it typically reverts back to a clear appearance. Symptoms last 5 to 10 days: Most colds are over in about a week, and symptoms typically improve steadily after the first few days. Common cold symptoms include a cough (which may be worse at night) and general lack of energy and appetite. You might also have a low fever, slight headache and slightly sore throat. If a fever is present, it’s low-grade: Adults don’t usually run a fever with a cold; kids sometimes do. If a fever is present, it’s likely to be a low-grade fever that is closer to 100 degrees F. Cold-related fevers usually occur at the beginning of the cold and does not persist through the duration of the cold. Antibiotics won’t help: All colds are caused by viruses. Antibiotics kill bacteria, so an antibiotic won’t help your cold at all. In fact, taking antibiotics for a cold can actually contribute to the development of antibiotic-resistant bacteria, a serious public health problem. A Sinus Infection Sinus infections can be acute or chronic. An acute sinus infection is one that lasts less than four weeks. Chronic sinus infections are those that last longer than 12 weeks, or occur more than three times a year. Symptoms of a sinus infection include: Thick green or yellow nasal drainage. Thick nasal mucus that continues for a period of several days is likely due to a sinus infection. This nasal drainage can sometimes also cause a sore throat; the nose and throat are connected, and nasal drainage can drip down into the back of the throat, creating irritation. That’s also what causes the bad breath that frequently accompanies sinus infections. Headache, face pain or teeth pain. You have four paired paranasal sinuses and they’re all located around your eyes: The maxillary sinuses are under your eyes, the front sinuses above the eyes, the ethmoid sinuses between the eyes and the sphenoid sinuses behind the eyes. Any (or all) of these sinuses can be congested and clogged during a sinus infection. No wonder your head and face often ache during a sinus infection! Some people feel a sinus infection in their teeth too. That’s because the upper rear teeth are located near the sinuses, so pressure in the sinuses creates pressure on the teeth. Symptoms last longer than 10 days. If your cold-like symptoms have lasted more than 10 days, you probably have a sinus infection. A “cold” that gets worse instead of better over a week to 10 days may also be a sinus infection. Antibiotics may help. Because sinus infections can be caused by bacteria, antibiotics can be used to kill the bacteria and treat the underlying cause of your illness. However, not all sinus infections require antibiotics. Viruses can cause sinus infections too, and if you have viral sinusitis, antibiotics won’t help at all. Plus, many bacterial sinus infections resolve on their own, without antibiotic treatment. Depending on your symptoms and history, your healthcare provider may prescribe antibiotics, or may recommend waiting a few days to see if the infection will clear up. Rest, fluids and pain- and fever-relieving medications, such as acetaminophen and ibuprofen, can be used to treat both colds and sinus infections. Also helpful: warm, steamy showers or baths. If these treatments don’t relieve your pain and discomfort, it’s time to see a healthcare provider for an official diagnosis and medical assistance.