Once a virus takes hold, your immune system attacks, and that process causes swelling, congestion and mucus. (Bigstock)

Your nose is under constant assault from the viruses passed around this time of year amid dry, indoor heat. Here’s how to alleviate the most common nasal nightmares.

Cold virus. The culprit behind most colds is one of the many rhinoviruses in the environment. You catch a cold when a virus is deposited directly in your nose or eyes (tears drain into the nasal cavity) and begin to multiply in the lining of your nasal passages. Most often, rubbing your nose or eyes after touching something the virus has been left on is the gateway in. That’s why frequent hand washing is the No. 1 tip for preventing colds; rhinoviruses can last up to three hours on your skin or on objects such as door handles. Once the virus takes hold, your immune system attacks, and it’s a side effect of that process that causes swelling, congestion and mucus.

What to do. Drinking fluids helps thin mucus and unstuff your nose. Also, try a saline nose spray; it’s safe to use as often as you need it. Need stronger measures? Congestion is often caused by engorged blood vessels, so a decongestant is in order. Experts recommend spray decongestants over pills because they attack the problem locally rather than affect your entire system. Pick one with oxymetazoline, such as Afrin, Vicks Sinex or a generic. Be sure to use them as directed; the sprays can cause rebound swelling if used longer than three days. If you prefer pills, try pseudoephedrine (Sudafed or generic), which is nonprescription but is kept behind pharmacy counters. If you have hypertension or glaucoma, talk to your doctor before using it.

Sinusitis. This inflammation of the lining of the sinuses is caused by allergies, irritation or an infection. You’ll feel as if your head is stuffed up, not just your nose, and you might have tenderness in your cheeks, upper jaw or around your eyes.

What to do. Doctors usually encourage sufferers to try home or over-the-counter remedies — say, a painkiller and a decongestant. Most cases are viral, not bacterial, so antibiotics won’t help. Sinusitis usually clears up in about 10 days. If symptoms last longer, see your doctor.

Copyright 2014. Consumers Union of United States Inc.

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