Scratching can be catching, new research has shown.
Just like yawns, scratching an itch is contagious, say scientists.
The sight of someone trying to get rid of an itch can lead us to scratch ourselves - without even knowing it.
Researchers tested 30 volunteers to see if visual cues could trigger itching and compel them to scratch.
Participants were shown "itch-related" images such as ants, fleas, or skin rashes, or neutral photos including butterflies and healthy skin.
Some pictures only showed a possible cause of itching, such as ants crawling on the skin, while others depicted itchy people scratching or washing their hands.
TIPS: Scroll down to find out how you can cure skin irritations
As volunteers looked at each image, they were asked how itchy they felt. The scientists also recorded the number of times participants scratched themselves.
The results, published in the British Journal of Dermatology, showed that visual images alone can trigger itch sensations.
But it was watching another person scratching, rather than just seeing the cause of the itch, that led the volunteers to scratch themselves.
Lead scientist Professor Francis McGlone, from Liverpool John Moores University, said: "The results of the present study confirm that visual cues pertaining to itch-related events are effective in transmitting the sensation of itch from the visual to the somatosensory domain (the body's system relating to the sensation of touch) and provoking a scratch response.
"The results suggest that, whereas the sensation of itch may be effectively transmitted by viewing others experiencing itch-related stimuli on the body, the desire to scratch is more effectively provoked by viewing others' scratching.
"Our findings may help to improve the efficiency of treatment programmes for people suffering from chronic itch. Knowing the specific triggers of an individual's chronic itch and how visual stimuli translate to the physical may also provide insight into the mechanisms of 'psychosomatic itch', in which there are no physical triggers."
Nina Goad, of the British Association of Dermatologists, said: "Itch is often the worst symptom for people with skin disorders, and any research into its causes that may lead to new methods of alleviation will be greatly welcomed by the millions of skin patients.
"Combining elements of psychology with dermatology is an increasingly important area of research."
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Verallo-Rowell says the main complaint she hears during allergy season is puffiness around the eyes. When pollen or other irritants get into your eyes, it causes inflammation, which can also make eyes red and itchy. She suggests holding a cotton ball drenched in cool water over your eyes. If your symptoms persist for more than a couple of days, switch to lukewarm water -- rather than constricting the blood vessels to reduce inflammation, warmer water will help flush away toxin buildup. You'll also want to check the ingredients in any eye makeup or skincare products, says Deborah Burnes, <a href="http://www.huffingtonpost.com/deborah-burnes" target="_hplink">HuffPost blogger</a>, CEO and Founder of <a href="https://sumbody.com/" target="_hplink">sumbody</a> and author of "Look Great Live Green." "The active [ingredients] in many wrinkle removers are designed to plump up wrinkles," she told The Huffington Post. "That can backfire for people with bags under their eyes." Lack of sleep, or sleeping face down can also cause puffiness. One thing that might help is raising the head of your bed to alleviate some of the pooling of blood in the face while you sleep, says Burnes. Caffeine can also help. The stimulant gets circulation flowing and breaks up old deposits in your skin, she says. You can drench a cotton round in cooled coffee and place it over your eyes, or simply rub some underneath your eyes with your fingertips, she says. Just make sure to wash your face after, or your coffee stains will be mistaken for dark circles! To kick the de-puffing up a notch, Burnes recommends mixing coffee grounds, licorice root and a pinch of turmeric in an empty tea bag, steeping it in hot water and then applying the tea bag to the eye area once it's cool. (The water can even be used as a toner, she says.)
Red, Itchy, Watery Eyes
Many sniffly, sneezy allergy sufferers are quick to look for nasal relief, but will ignore their <a href="http://www.webmd.com/allergies/eye-allergies" target="_hplink">red, itchy, watery eyes</a>. Like any allergy symptom, itchiness is triggered when the eyes come into contact with an allergen, and the body's immune system essentially <a href="http://www.acaai.org/allergist/allergies/Types/eye-allergies/Pages/default.aspx" target="_hplink">"overreacts" to this perceived threat</a>. Even though they're itchy, it's important not to rub your eyes when you're experiencing allergy symptoms, because that will likely <a href="http://www.webmd.com/allergies/eye-allergies" target="_hplink">only make it worse</a>. A cool compress can help these symptoms as well. Verallo-Rowell suggest investing in a pair of wraparound sunglasses, like the type cyclists wear. They'll help prevent allergens from irritating the eyes in the first place, she says.
You'll naturally look rosier around the nose when you're congested, and not in a good way. The right concealer can do wonders; skip those with pink hues in favor for one with <a href="http://www.webmd.com/allergies/living-with-allergies-11/beauty-tips?page=2" target="_hplink">yellow undertones</a>. Drinking tomato juice may also help reduce redness all over, says Burnes, due to the <a href="http://www.bbc.co.uk/sn/humanbody/truthaboutfood/young/tomatoes.shtml" target="_hplink">skin-protecting benefits of lycopene</a>. She also recommends a calming mask for your skin made of equal parts yogurt and honey. You can add coconut water or a few drops of avocado oil in as well, for extra hydration. "One thing that happens as we get these allergies and our nose is runny and our eyes our red, our skin also gets dehydrated," she says. "Dry skin creates a vicious cycle of itching more and being irritated more and being uncomfortable."
Skin allergies, or allergic contact dermatitis, occurs when your skin comes in contact with an allergen, which can be anything from poison ivy to that new perfume. It often causes an <a href="http://www.mayoclinic.com/health/skin-rash/SN00016&slide=4" target="_hplink">itchy, red rash with bumps</a> or even blisters, according to Mayo Clinic. Poison ivy causes the worst reaction, says Verallo-Rowell, but you can have milder reactions to many plants, including pine trees, which can be very allergenic for some people. In general, she says, a plant with a strong aroma carries a higher risk of irritating your skin. The most important remedy: Avoid spreading the rash. Wash off any irritating plant remnants or sap with water only, she says, as some soaps could exacerbate the problem. <em>Flickr photo by <a href="http://www.flickr.com/photos/mullica/5821076236/" target="_hplink">Robert Benner</a></em>
If your skin is just itchy and you don't notice any rash, check to make sure you're not simply suffering from dry skin. However, the urge to scratch can be due to contact with an allergen, including <a href="http://www.mayoclinic.com/health/itchy-skin/DS00847/DSECTION=causes" target="_hplink">wool, chemicals and some soaps</a>, according to Mayo Clinic. Now that spring is here, budding plants pose more of a chance of irritating the skin, says Verallo-Rowell. After washing off any irritated area, cucumber -- without the rind -- can be very soothing when placed on itchy skin. She also suggests storing coconut oil in the fridge so it hardens into a butter-like consistency. "Spoon it on the skin while it's still nice and cool and it melts and softens and soothes -- and has its own antioxidants!"
First off, make sure you're plenty hydrated and -- be honest about this one -- getting enough sleep. But those shadowy bags under your eyes can truly be due to allergies. <a href="http://www.menshealth.com/allergycenter/eyes-dark-circles.php" target="_hplink">Nasal congestion can cause blood to pool</a> in the area under the eyes, which can show through the very thin skin there. Puffiness can also contribute to under-eye circles, says Verallo-Rowell. Commit to sleeping eight hours a night during allergy season so you're really rebooting, she says, and add extra fruits and veggies to your diet. The antioxidant powers in vitamins C and E can help reduce both puffiness and dark circles.