When all is calm
At your fave cafe, specks of pollen from the flowers on your table are carried through the air and, as you breathe in, pass the little hairs in your nostrils – your body’s filtration system. Most will be trapped, but a few might get through and settle in the mucus in the lining of your nose. Or you might be coming down with something.
What happens next is a splitsecond chain of events that expel the ‘contaminated’ mucus,relieve your body of irritation and clear your airways. No matter why you’re sneezing, the first thing to trigger the sneeze is the release of histamines. These neurotransmitters are released by cells in response to aggravation; they’re the same chemicals that cause your skin to become red and itchy when you’re bitten by a mozzie.
The histamines irritate the cells in your nose that, through a network of nerves, send signals to the medulla, the lower section of your brain, to prepare your body to sneeze. In the next few milliseconds your face, throat and neck muscles involuntarily contract (sneezing is a reflex action). The pharyngeal and tracheal muscles in your throat are activated, your nasal and oral passages open and your chest expands, filling your lungs with air.
Your chest muscles compress your lungs; air is blasted up and violently expelled up to 160km an hour (if you’ve had a baby, sneezing may bring on light bladder leakage – you might want to keep the Poise on hand). You’ll keep sneezing until the irritation has cleared. Along with air, between 2000 and 5000 droplets of mucus, saliva and germs can shoot out and fly through the air for up to 1.5m. The particles are light enough to travel further and will settle on any nearby surface. This is why you should cover your nose and mouth (with the inside of your elbow), then wash your hands to avoid spreading germs.
Are you getting sick, or is your body simply responding to an allergen? Remember those histamines, the neurotransmitters that kicked off the sneeze? They could also cause your eyes, nose and throat to become irritated. If these are your only symptoms, you should be OK, but if you start to have chills, a cough, fever or headaches, a cold could be on its way.