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Chigger Bites

These tiny critters hide in brush and attach to tender skin. When chiggers bite, they inject stuff that turns your skin to liquid they can use for food. The result: Dozens of tiny, itchy bites above your sock lines, waistline, or around folds of skin. They usually stick around for 3 or 4 days. To cut that down, scrub the area with soap and water. Calamine lotion, a liquid bandage, or hydrocortisone cream can also ease the itch.

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Brown Recluse Spider Bite

Bites from these brown spiders with violin-like marks on their backs usually heal on their own within 3 weeks. But sometimes venom from the bite kills the skin around it. (Doctors call this a necrotic lesion.) When this happens, the area around the bite turns blue and sinks in. A blister may form in the center. The sore can grow by several inches over about 10 days, but it may take months to heal. Call a doctor if you think one bit you.

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Fire Ant Bites

Unlike other ants, they don’t just bite. They sting, too. Usually after you step on one of their mounds. First the bite will burn. Then it’ll cause pimple-like bumps (pustules) that blister and itch like crazy for a week or so. Sometimes the whole area gets inflamed and painful. In rare cases, an allergic reaction can cause fever, weakness, and breathing problems. That’s serious, so get to a doctor right away.

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Lyme Disease Rash

You can get it when a deer tick bites you. It may take a few days to a month, but you might notice a bull’s-eye shaped rash. It could get as big as 12 inches across, but it shouldn’t itch. You could also get fever, chills, fatigue, body aches, and a headache. Get to a doctor right away if you think you have it. Early treatment with antibiotics seems to help, and it can cause joint pain and temporary paralysis if you don’t treat it.

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Scabies

You probably won’t see the mite that causes this condition. It uses its 8 legs to burrow into the top layer of your skin to feed. Your body responds with an itchy rash. You might get it from another person if you touch their skin, or from sheets, clothes, or furniture. A doctor can tell you for sure if you have it. They’ll prescribe special medication to get rid of it. Make sure you treat things you touch at home to prevent reinfestation.

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Swimmer's Itch

Parasites that live on snails and water birds (like ducks and geese) sometimes get into lakes or ponds where you swim. They burrow into your skin. They die quickly, but your body’s reaction causes red, itchy bumps. It isn’t serious and should go away in a week or two. You can control the itch with over-the-counter creams. Talk to your doctor if it lasts longer or if it seems to be infected and painful.

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Molluscum Contagiosum

This virus loves warm, humid places. You get it from someone else’s skin or infected towels, clothes, or gym mats. It normally causes around 15 bumps, but you may get as many as 100 if your immune system is weak. They’re pinkish with a dimple in the center that could have a cheesy gunk inside. It usually goes away without treatment in a year or so, but your doctor might suggest drugs or minor surgery in some cases.

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Ringworm

The fungus that causes it lives on floors, countertops, clothing, furniture, towels, sheets, pets, and even on your skin until a scratch lets it in. It causes red, itchy rashes that could sting anywhere on your body. Scalp ringworm causes flaky sores that look like dandruff. You may get it from other people, but it’s less likely if you wash and dry yourself thoroughly. Antifungal creams and pills might get rid of it, but it can return.

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Hand-Foot-and-Mouth Disease

This virus most often affects young children. It causes a red rash on their hands, feet, and sometimes their bottoms. It doesn’t itch but may blister. Your child might have a fever, sore throat, and painful, blistering mouth sores. It usually goes away on its own in 7 to 10 days, but pain pills or ointments can help keep your child comfortable.

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Impetigo

Young kids most often get these sores on their face, neck, hands, or bottom. They may be wet and red, crusty and yellow, or blistered and unbroken with clear fluid. The bacteria that cause it get in through a cut, scrape, or irritated skin. Impetigo can spread to other people who touch the sores. Proper washing can help prevent it. Doctors use antibiotics in a pill or ointment to kill the bacteria.

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Jellyfish Sting

Long finger-like jellyfish tentacles can inject poison into your skin when you brush past them. They leave red or purplish tracks that might first burn, throb, itch, and swell. Rinse the sting with vinegar, carefully pluck out any barbs you can see, and soak the area in hot water (110 F or so). See a doctor if you feel nauseated, weak, confused, or have trouble breathing.

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Wild Parsnip Rash

You’ll spot this plant with large bunches of yellow flowers on a thick stem in sunny spots along highways and other open areas. Its sap could trigger a kind of skin burn that gets red and may blister. Serious cases might discolor your skin for months or more. A wet, cool, cloth or moisturizer cream should help the pain. Talk to your doctor about bad blisters, or if they last more than 2 weeks.

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Christmas Tree Rash

Also known as pityriasis rosea, you’re more likely to get if you’re pregnant or between ages 10 and 35. Doctors don’t know for sure what causes it, though it may be a virus. It starts with a patch on your belly, chest, thigh, or back, and often spreads. On your back, it can grow into the shape of a Christmas tree. It might get itchy, but it should go away without treatment in a month or two.

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Drug Rash

It usually shows up within a week after you start a new drug. Just a few spots can become a big patch. Antibiotics and water pills (also called diuretics) are common triggers. Some drugs only cause a reaction when you get in the sun. It should go away in a few days or weeks once you stop the medication, but talk to your doctor before you do that. If you find it hard to breathe or have other serious reactions, get to an emergency room.

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Goosebumps

They’re a leftover from our ancient relatives who were hairier than us. When they got cold, their hair would stand up, which helped warm them up. It also made them look bigger when they ran into predators. All that’s left for us are the follicles that pucker around each widely spaced hair when we’re chilly or scared.

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Lichen Planus

These firm, shiny, reddish bumps, often with tiny white lines, can show up on your lower back, ankle, wrist, or all over. In time, thick patches of crusty, itchy skin may form. Doctors don’t really know the causes, but it could be that your immune system mistakenly attacks your body. There’s no cure, but your doctor might treat symptoms with steroids, antihistamines, anti-itch pills and creams, and light therapy for widespread disease.