4. You're nodding off during the day but not at night
Allergies may be the problem. More than 40 percent of sufferers toss and turn at night, found a study published in the Archives of Internal Medicine. According to researchers, congestion coupled with stimulating medications, like certain decongestants, can make it hard to fall asleep. "Because your immune system is working overtime, you may also feel exhausted," says Sublett.
Take action: First, check to make sure that the antihistamine you're taking is non-sedating (read labels and look for a brand with the active ingredient loratadine). In the evening, skip decongestants with pseudoephedrine or phenylephrine, which can keep you awake. Then, for a better night's rest, ban allergens from your bedroom by closing your windows and running the air conditioner on the "recycle" setting. "That cleans the air, trapping any stray particles," says Sublett. (Be sure to change the filter every three months.) Also, shower before bed rather than in the a.m. so you can rinse off pollen that may have accumulated on your hair and skin.
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5. You can't stop clearing your throat
That postnasal drip could signal a cold (especially if you have a low-grade fever), allergies, or even a sinus infection.
Take action: Start with a neti pot and add an antihistamine. Then, if symptoms of allergies continue, consult a physician. "You may need a prescription nasal steroid spray to relieve the inflammation that leads to excess mucus," says Corn. If you still have allergy symptoms after three weeks, see an allergist for skin or blood testing to determine what you're allergic to. She may recommend allergy shots and refer you to an ear, nose, and throat specialist to check for a deviated septum or polyps—non-cancerous growths in your sinus cavity or nasal passages.
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6. Your eyes and skin are itching like crazy
Blame allergies again. "That flood of histamine causes tiny blood vessels in your eyes and skin to dilate and leak, which can lead to itching and redness," says Sublett.
Take action: Try a targeted approach. "Use preservative-free artificial tears, like those from Clear Eyes and Visine, first," says Corn. "If you don't feel better, see an allergist for prescription antihistamine eyedrops." For your skin, pick up an over-the-counter oral antihistamine and a cortisone cream, like Cortizone-10 ($9; drugstore.com). If the itching doesn't go away after a few days, see an allergist, who can prescribe a topical steroid cream. While you wait for your appointment, take warm showers instead of hot ones, which can dehydrate skin and make you itchier. Use mild soap and fragrance-free lotions, like those by Cetaphil, and skip the mascara and eyeliner, which can cause even more irritation.
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