It begins as a tickle but can quickly elevate to epic proportions.
And try as you might, you often can't suppress a cough, especially when you're at the movies, in the library or in a crowded lecture hall--not to mention when you'd just like a decent night's sleep.
(Don't expect relief right away. The experts say the coughing season, which usually ends in the beginning of March, is dragging on a bit longer this year.)
There's more to the cough reflex than meets the ear.
Here are some of the facts, along with experts' advice about stifling yourself when an irritant--mucus, dust, smoke, an allergen, a foreign body--enters the throat or the air passages of the lungs, the glottis opens--allowing deep inspiration--and then closes, the lungs contract and compress the air, then the glottis opens and air is expelled, producing, ta-dum, a cough:
* A cough is a protective mechanism, a way for the body to get irritants and debris out of the airway. And sometimes, the cough is a very dramatic protective mechanism. Consider the Indiana man who was told that the bullet lodged in his chest was too risky to remove. Then at church one day, he reportedly coughed up the .38 caliber slug.
And in a bizarre cough-related case, last week a Ventura County jury found Alfred Pohlmeier guilty of second-degree murder for strangling his wife of 62 years to quiet her nagging cough.
* Garden-variety coughs often get worse at night. There's a simple explanation: When you lie flat, "mucus drains and pools down at the base of the throat," says Dr. Arleen Rockoff, an internist and infectious disease specialist at Kaiser Permanente-Woodland Hills. You cough to get rid of the gunk.
* Coughs are part and parcel of colds, sometimes lasting for weeks after the cold has gone away.
* Coughs can be associated with a variety of other conditions, such as postnasal drip, allergies, viral infection, sinus infection, asthma and gastroesophageal reflux disease, or GERD (in which stomach acid splashes back up). Coughs can also be a symptom of lung cancer or a side effect of ACE inhibitors, medicines prescribed to treat high blood pressure and some heart problems.
"But now a new generation of ACE inhibitors does not have cough as a side effect," says Dr. Harry Cohen, internist on staff at Encino-Tarzana Regional Medical Center and USC assistant clinical professor of medicine.
* Coughs come in two types: wet, or productive, and dry, or hacking.
"Wet coughs bring up sputum, and it's more likely to be coming from your bronchial tree and your lungs," Cohen says.
Dry coughs can point to sinus problems.
* Productive coughs, or so the thinking goes, shouldn't be constantly suppressed because they help clear the airways. But when you've gotta sleep, you might consider self-treatment.
* Last year, Americans spent $1.8 billion on cough and cold remedies, and $388 million more on cough drops, says the Information Resources Inc., a Chicago-based marketing research firm.
* When shopping for remedies, know the lingo. Expectorants loosen mucus. Sup-pressants are for dry coughs.
* Be kind to your throat--avoid smokers and dusty environments.
* Coughs with high fever, coughs with wheezing, coughs accompanied by pressure in the head, recurrent or chronic coughs, and coughs accompanied by dizziness or painful teeth all warrant your doctor's attention.
* If you think your kid is coughing nearly all the time, you may be right, says Dr. Neal Kaufman, pediatrician at Cedars-Sinai Medical Center and UCLA professor of pediatrics. "The average child gets four to six colds a year, and a cough after a cold can last four to six weeks." You do the math.