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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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What Makes Some People Susceptible to Allergies?
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What Makes Some People Susceptible to Allergies?
Why some people are allergic to certain things while others are not can be a difficult topic to understand. For example, a dog can jump into your lap and, just like that, you will start to sneeze and your eyes will drip. All of this will force you to toss Fido aside in search of a tissue box. Meanwhile, your friend or neighbor experiences none of the above effects.Why is this? There are three main reasons: inherited genes, environment and age.
It's in the Genes
Allergies can often be blamed on mom and dad. The tendency to become allergic is inherited, and the chances that you also will be allergic increase from about 50 percent when one parent is allergic to 75 to 80 percent when both parents have allergies.
Tell your friends you're "atopic," meaning that you have inherited the tendency to have an allergy.
(And hope that none of your friends know Greek, as "atopic" derives from the Greek word for "strange.")
But you needn't feel strange...or alone. The American College of Allergy, Asthma and Immunology (ACAAI) estimates that as many as 50 million Americans suffer with asthma, hay fever, or other allergy-related conditions.
So, the family genes are stacked against you. Does this mean instant sniffles? Not always. Don't forget, even if you have a 60 percent chance of developing allergies, you also have a 40 percent chance of not developing them. That's why Fido turns your nose and eyes into streams while your brother is pretty much dry. In the genetic roll of dice, he came out the winner.
Environment Counts ...
There's more to developing allergies than heredity. What you become allergic to is based on when and how much you're exposed to a substance and how much of it you're exposed to.
For example, say you have a tendency to be allergic to mold spores. You may have no allergy symptoms when you're living alone in your spic 'n' span apartment, but when a roommate moves in, bringing along a jungle of house-plants, an old mattress, and a humidifier (to keep her skin moist) you soon become a symphony of sneezes and snorts. What happened? You had endured a certain amount of exposure to mold spores without a problem, but once the scales were tipped by the onslaught of your roommate's mold-bearing stuff, your immune system kicked into high gear.
... As Does Age
How old you are when you're exposed is critical, and viruses may also play a role. Recent studies show that heavy exposure early in life -- before age 2 -- may be protective against animal allergies and asthma.
Now that we've discovered the source of allergies and what makes certain people susceptible to them, it's time to look at specific types of allergies. First up is the most common type of allergy -- allergic rhinitis.
Chronic and Acute Allergies |
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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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SYMPTOM CHECKER:
Abdominal Bloating Abdominal Fullness Prematurely Afte... Abdominal Lumps Abdominal Mass Abdominal Pain Abdominal Rigidity Abdominal Sounds Abdominal Swelling Abnormal Posturing Abnormal Tooth Shape Abnormally Dark Or Light Skin Absent Menstruation Absent Thirst Agitation Ambiguous Genitalia Ankle Pain Appetite Decrease Appetite Increase Apraxia Arachnodactyly Armpit Lump Autistic Behavior Babinski's Reflex Bed Wetting Belching Binge Eating Blackheads Bleeding Gums Bleeding Into The Skin Blindness Blockage Of Leg Arteries Blood In The Semen Blood in Urine Bloody Or Tarry Stools Bone Pain Or Tenderness Bounding Pulse Bowel Incontinence Breast Lump Breast Pain Breath Odor Breath Sounds Breathing - Slowed Or Stopped Breathing Difficulty Breathing Difficulty When Lying Dow... 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:
Aarskog Syndrome Aase Syndrome Abdominal Aortic Aneurysm ABO Incompatibility Abortion - Complete Abortion - Elective Or Therapeutic Abortion - Incomplete Abortion - Infected Abortion - Threatened Abscess Acanthosis Nigricans Achalasia Achilles Tendinitis Achondrogenesis Achondroplasia Acidosis Acne Acoustic Neuroma Acoustic Trauma Acquired Platelet Function Defect Acrodermatitis Acrodysostosis Acromegaly Actinic Keratosis Actinomycosis Acute Adrenal Crisis Acute Arterial Occlusion - Kidney Acute Bilateral Obstructive Uropath... Acute Bronchitis Acute Cerebellar Ataxia Acute Cholecystitis (Gallstones) Acute Cytomegalovirus (CMV) Infecti... Acute Gouty Arthritis Acute HIV Infection Acute Interstitial Nephritis Not NS... Acute Kidney Failure Acute Lymphocytic Leukemia (ALL) Acute Mountain Sickness Acute Myeloid Leukemia Acute Nephritic Syndrome Acute Pancreatitis Acute Tubular Necrosis Acute Unilateral Obstructive Uropat... Acute Upper Airway Obstruction Addison’s Disease Adenomyosis Adhesion Adjustment Disorder Adolescent Depression Adolescent Pregnancy Adrenocortical Carcinoma Adrenoleukodystrophy Adult Still's Disease Agammaglobulinemia Age-related Hearing Loss Agoraphobia Agranulocytosis Aicardi Syndrome AIDS Albinism Alcohol Withdrawal Alcoholic Cardiomyopathy Alcoholic Ketoacidosis Alcoholic Liver Disease Alcoholic Neuropathy Alcoholism Alkalosis Alkaptonuria Allergic Conjunctivitis Allergic Rhinitis Allergic Vasculitis Allergies Allergy To Mold - Dander - Dust Alopecia Areata Alpha-1 Antitrypsin Deficiency Alport Syndrome Alström Syndrome Alveolar Abnormalities Alzheimer’s Disease Amaurosis Fugax Amblyopia Amebiasis Amebic Liver Abscess Amelogenesis Imperfecta Amenorrhea Amniotic Constriction Bands Amphetamine Or Sympathomimetic Into... Amyotrophic Lateral Sclerosis Anal Fissure Analgesic Nephropathy Anaphylaxis Anaplastic Thyroid Cancer Androgen Insensitivity Syndrome Anemia Anemia - B12 Deficiency Anemia Of Chronic Disease Anencephaly Aneurysm Aneurysm In The Brain Angina Angiodysplasia Of The Colon Angioedema Ankylosing Spondylitis Annular Pancreas Anorchia Anorectal Abscess Anorexia Nervosa Anthrax Antisocial Personality Disorder Aortic Arch Syndrome Aortic Dissection Aortic Insufficiency Aortic Stenosis Apert Syndrome Apnea Of Prematurity Apoplexy Appendicitis ARDS (acute Respiratory Distress Sy... Arrhenoblastoma of the Ovary Arrhythmias Arterial Embolism Arterial Insufficiency Arteriosclerosis Of The Extremities Arteriovenous Malformation - Cerebr... Arthritis Asbestos-related Pleural Effusion Asbestosis Ascariasis Ascites Aseptic Meningitis Aseptic Necrosis Asherman Synd