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Lundgren, Linnea, and Jeff Wald. "Allergy Basics." 02 May 2006. HowStuffWorks.com. <http://health.howstuffworks.com/how-allergies-work.htm> 17 May 2008.
by Linnea Lundgren and Jeff Wald, MD
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Skin Allergies
The skin is your largest organ and an important defender against invaders. It is constantly bombarded and usually fends off trouble quite successfully. Sometimes, however, an allergen gets the best of your skin, causing a reaction. This section will explore skin allergies and the reactions they cause.Skin Allergy Symptoms
Symptoms can include a rash or hives, or swelling, itching, and cracking of the skin. Our hands, arms, neck, and face come in contact with so many substances every day that they are the most common sites for an allergic skin reaction, but no part of your anatomy is immune. A skin reaction that is the result of contact with an allergen is called allergic contact dermatitis. (By contrast, a skin reaction caused by contact with a substance that is harsh or caustic is called irritant contact dermatitis and does not involve allergies or the immune system.)
The National Institute of Health currently estimate that 20 percent of infants and children exhibit symptoms of atopic dermatitis. |
Potential allergens exist everywhere. Many can be rounded up in the bathroom cabinet: nickel/chrome in jewelry and snaps; latex found in condoms, rubber gloves, bandages, and rubber bands; chemicals in cosmetics, toiletries, and perfumes; hair products, including hair dye; and laundry detergent and fabric softeners. The great outdoors hosts such potential villains as poison oak, poison sumac, and poison ivy.
Identifying the exact cause of allergic contact dermatitis can be difficult because your skin comes in contact with hundreds of suspects a day and first reactions may occur hours or days after the initial contact. In some cases, a reaction doesn't occur until weeks or months of prolonged use. Luckily, contact dermatitis isn't named contact for nothing. Many allergens leave a trail to follow. The location of the rash, hives, or itch will help you to put the suspects in a lineup.
How about a rash that develops under your arms? The possible causes: lotion, deodorant/antiperspirant, elastic straps in clothes, a bra's underwire, new fabrics, etc. Like so much in the allergy world, a little observation can go a long way toward discovering what is irritating you.
Pinpointing and avoiding contact with the allergen is the primary treatment for allergic contact dermatitis. However, if the rash spreads or if you develop hives or experience uncontrollable itching and the skin becomes red, tender, and damaged, see your physician.
Exploring Eczema
Symptoms include red, itchy, dry, scaly patches most frequently on the face, arms, legs, and scalp. Infants and children are particularly susceptible to eczema, but the vast majority of children who have eczema outgrow it. It's clear that there's a connection between eczema and allergies, since 70 percent of those who have this skin condition have a family history of allergies or asthma. And one-third of those with eczema eventually will develop allergic rhinitis or asthma.
There is no cure for eczema. The best preventive measures are to moistureize your skin so it doesn't dry out and to pinpoint and avoid substances that seem to irritate your skin or trigger the rash. Additionally, topical medications containing steroids can help control itching, as can oral antihistamines.
Your skin is always being exposed to potential allergens. Allergic contact dermatitis and eczema are two different types of skin allergies. Identifying and treating them is a matter of being informed and knowledgeable.
Had a bad reaction to a wedge of cheese? A glass of milk? In the next section, we will look at food allergies and how to deal with them.
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Please copy/paste the following text to properly cite this How Stuff Works article:
Lundgren, Linnea, and Jeff Wald. "Allergy Basics." 02 May 2006. HowStuffWorks.com. <http://health.howstuffworks.com/how-allergies-work.htm> 17 May 2008.
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Breathing That Sounds Abnormal Broad Nasal Bridge Bulging Fontanelles Bullae Chemosis Chest Pain Chills Clammy Skin Claw Foot Claw Hand Cloudy Cornea Clubbing Of The Fingers Or Toes Cold Intolerance Coloboma Of The Iris Comedones Confusion Constipation Contracture Deformity Coughing Coughing Up Blood Crying Excessively in Infants Cyst Decerebrate Posture Decorticate Posture Decreased Consciousness Decreased Urine Output Delayed Growth Delayed or Absent Tooth Formation Depression Diarrhea Difficulty with Urination Dizziness Drooling Drowsiness Dry Eyes Dry Hair Dry Skin Ear Discharge Earache Earlobe Creases Elbow Pain Epicanthal Folds Erection Problems Erosion Excessive Or Unwanted Hair In Women Excessive Thirst Excessive Urination Excessive Urination at Night Excessively Large Fontanelles Eye Burning, Itching and Discharge Eye Pain Eye Redness Eye Slant Eyelid Drooping Eyes That Bulge Face Pain Facial Paralysis Facial Swelling Fainting Fatigue Female Sexual Dysfunction Fever Finger Pain Fingers That Change Color Flank Pain Floating Stools Focal Neurological Deficits Foot Pain Foot, Leg, And Ankle Swelling Foul Smelling Stools Frequent Or Urgent Urination Frontal Bossing Gas (Flatulence) Gastrointestinal Bleeding Genital Sores (Female) Genital Sores (Male) Groin Lumps Groin Pain Gynecomastia Hair Loss Hallucinations Hand Or Foot Spasms Hand Tremors Headache Hearing Loss Heart Murmurs And Other Sounds Heart Palpitations Heartburn Heat Intolerance Heavy, Prolonged, or Irregular Mens... Heel Pain Hemolytic Crisis Hepatomegaly Heterochromia Hiccups Hip Pain Hoarseness Or Changing Voice Hump Behind The Shoulders Hyperactivity Hyperelastic Skin Hypermobile Joints Hyperventilation Hypotonia Impaired Smell Increased Head Circumference Indigestion Infantile Reflexes Intercostal Retractions Intertrigo Irritability Itching Jaundice (Yellow Skin) Joint Pain Joint Swelling Knee Pain Leg Pain Lichenified Limited Range Of Motion Lordosis Low Nasal Bridge Lower Back Pain Macule Malaise Memory Loss Metopic Ridge Microcephaly Micrognathia Morbid Obesity Morning Sickness Moro Reflex Motormental Retardation Mouth Sores Muscle Aches Muscle Atrophy Muscle Cramps Muscle Function Loss Muscle Twitching Nail Abnormalities Nasal Congestion Nasal Discharge Nasal Flaring Natal Teeth Nausea And Vomiting Neck Lumps Neck Pain Night Blindness Nightmares Nikolsky’s Sign Nipple Discharge Nodules Nosebleed Numbness And Tingling Obesity Opisthotonos Pain During Sexual Intercourse Painful Menstrual Periods Painful Urination Pale or Clay-Colored Stools Paleness Papule Patches Patchy Skin Color Pectus Carinatum Pectus Excavatum Penis Pain Photophobia Pilonidal Dimple Pinna Abnormalities And Low-set Ear... Point Tenderness Polydactyly Polyhydramnios Poor Feeding In Infants Preauricular Tag Or Pit Premenstrual Breast Tenderness and ... Prognathism Pupils That Are Different Sizes Purpura Pustules Rapid Shallow Breathing Rash in a Child Under 2 Years Rashes Rib Cage Pain Ridged Sutures Scales Scrotal Swelling Seizures Sensorineural Deafness Separated Sutures Shin Splints Short Philtrum Short Stature Shoulder Pain Simian Crease Skeletal Limb Abnormalities Skin Blushing/flushing Skin Discoloration Skin Lumps Skin Turgor Sleeping Difficulty Sneezing Snoring Sore Throat Spasticity Speech Impairment (adult) Splenomegaly Splinter Hemorrhages Strange Behavior Stress And Anxiety Striae Subcutaneous Emphysema Sunburn Sunken Fontanelles Supernumerary Nipples Swallowing Difficulty Swallowing Pain Or Burning Sweating Sweating Decrease Swelling Swollen Glands Swollen Gums Taste Impairment Telangiectasia Tenesmus Testicle Lump Testicle Pain Tinnitus Tongue Problems Tooth Discoloration Toothaches Ulcers Uncontrollable Eye Movements Uncontrollable Movement Uncontrolled Or Slow Movement Uncoordinated Movement Unpredictable Or Jerky Movement Urinary Incontinence Urine Discoloration Vaginal Bleeding Between Periods Vaginal Bleeding In Pregnancy Vaginal Discharge Vaginal Itching Vesicles Vision Problems Vomiting Blood Walking Abnormalities Watery Eyes Weak or Absent Pulse Weakness Webbing Of The Fingers Or Toes Weight Gain Weight Loss Wheezing White Spots in the Pupil Whitehead Widely Spaced Teeth Wrinkles Wrist Pain Yawning
DISEASES AND CONDITIONS GLOSSARY:
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