Allergic Reaction
An allergic reaction is the body's way of responding to an "invader." When the body senses a foreign substance, called an antigen, the immune system is triggered. The immune system normally protects the body from harmful agents such as bacteria and toxins. Its overreaction to a harmless substance (an allergen) is called a hypersensitivity reaction, or an allergic, reaction.
See the complete A-Z list of all the allergy related information or browse the current list of select resources.
Allergy Related Resources
Allergies (Allergy) Articles
- Allergic Reaction
- Allergies FAQs
- Allergy Shots
- Allergy: Insect Sting
- Allergy: Poison Ivy, Oak, and Sumac
- Bee and Wasp Stings
- Contact Dermatitis
- Drug Allergy
- Food Allergy
- Foreign Body, Nose
- Hay Fever
- Hay Fever vs Cold
- Hives and Angioedema
- Indoor Allergens
- Insect Bites
- Severe Allergic Reaction (Anaphylactic Shock)
- Sinus Headache
- Sinus Infection
- Understanding Allergy and Hay Fever Medications
Allergies Medications
- acetaminophen and chlorpheniramine (Coricidin)
- acetaminophen and diphenhydramine (Anacin P.M. Aspirin Free, Coricidin Night Time Cold Relief, Excedrin PM and more)
- acetaminophen and phenyltoloxamine (Aceta-Gesic, Acuflex, Alpain and more)
- acetaminophen, clemastine, and pseudoephedrine (Tavist Allergy/Sinus/Headache)
- acetaminophen, diphenhydramine, and phenylephrine (Benadryl Allergy & Cold, Benadryl Allergy & Sinus Headache, Sudafed PE Severe Cold and more)
- acrivastine and pseudoephedrine (Semprex-D)
- azatadine (Optimine)
- azelastine nasal (Astelin, Astepro)
- beclomethasone nasal (Beconase AQ)
- brompheniramine (BroveX, BroveX CT, Dimetane and more)
- brompheniramine and pseudoephedrine (Andehist NR Syrup, Bidhist-D, Bromaline and more)
- budesonide nasal (Rhinocort Aqua)
- carbinoxamine (Palgic)
- cetirizine (All Day Allergy, All Day Allergy Children's, Indoor/Outdoor Allergy Relief and more)
- cetirizine and pseudoephedrine (All Day Allergy-D, Zyrtec-D)
- chlorpheniramine (AHist, Aller-Chlor, Allergy Relief and more)
- chlorpheniramine and codeine (Cotab A, Cotab AX, Notuss-AC and more)
- chlorpheniramine and methscopolamine (aeroHist, AlleRx DF Dose Pack, Ryneze)
- chlorpheniramine and phenylephrine (Allan Tannate Pediatric, Allerest PE, AlleRx and more)
- chlorpheniramine and pseudoephedrine (Allerest Maximum Strength, Dayquil Allergy, Deconamine and more)
- ciclesonide (nasal) (Omnaris)
- clemastine (Allerhist-1, Contac 12 Hour Allergy, Tavist and more)
- cromolyn sodium (inhalation) (Intal, Intal Inhaler)
- cromolyn sodium (nasal) (Nasalcrom, Nasalcrom Child)
- cromolyn sodium (oral) (Gastrocrom)
- cyproheptadine (Periactin)
- desloratadine (Clarinex, Clarinex Reditabs)
- desloratadine and pseudoephedrine (Clarinex-D 12 Hour, Clarinex-D 24 Hour)
- dexbrompheniramine and pseudoephedrine (Drixoral)
- dexbrompheniramine, hydrocodone, and phenylephrine (Cytuss-HC NR, H-C Tussive-NR, Histussin HC)
- dexchlorpheniramine and pseudoephedrine (AllerDur, Duotan PD, Tanafed DP)
- diphenhydramine and phenylephrine (Alahist LQ, Aldex-CT, Children's Triacting Night Time and more)
- diphenhydramine and pseudoephedrine (Benadryl Allergy Decongestant, Tavist NightTime Allergy)
- diphenhydramine, hydrocodone, and phenylephrine (Endal HD, Tussinate)
- emedastine ophthalmic (Emadine)
- epinastine ophthalmic (Elestat)
- epinephrine injection (Adrenalin, EpiPen 2-Pak, EpiPen Auto-Injector and more)
- fexofenadine (Allegra, Allegra ODT)
- fexofenadine and pseudoephedrine (Allegra -D 24 Hour, Allegra-D)
- flunisolide nasal (Nasarel)
- fluticasone nasal (Flonase, Veramyst)
- hydroxyzine (Vistaril)
- ipratropium (nasal) (Atrovent Nasal)
- levocetirizine (Xyzal)
- loratadine (Alavert, Claritin, Claritin 24 Hour Allergy and more)
- loratadine and pseudoephedrine (Claritin-D, Claritin-D 24 Hour)
- mometasone nasal (Nasonex)
- olopatadine (nasal) (Patanase)
- omalizumab (Xolair)
- phenylephrine (Ah-Chew D, Dimetapp Cold Drops, Lusonal and more)
- phenylephrine and promethazine (Phenergan VC, Promethazine VC Plain)
- phenylephrine and pyrilamine (Aldex D, Deconsal CT Tannate, K-Tan and more)
- phenylephrine nasal (Afrin 4 Hour Extra Moisturizing, Alconefrin-12, Alconefrin-25 and more)
- prednisolone (Bubbli-Pred, Flo-Pred, Hydeltrasol and more)
- prednisone (Meticorten, Sterapred, Sterapred DS)
- promethazine (oral) (Pentazine, Phenergan)
- promethazine (rectal) (Phenadoz, Promethegan)
- pseudoephedrine and triprolidine (Allerfrim, Allerphed, Altafed and more)
- triamcinolone (nasal) (Nasacort AQ)
- tripelennamine (PBZ, PBZ-SR)
- triprolidine (Zymine)
- xylometazoline nasal (Otrivin)
Allergies Images and Slideshows
- Allergic Contact Dermatitis (Arm) Picture
- Allergic Contact Dermatitis (Tattoo) Picture
- Allergic Contact Dermatitis Picture
- allergies allergy plants trees triggers
- Allergy Eye Relief
- allergy triggers life threatening emergencies
- healthy schedule home cleaning
- myths facts seasonal allergies
- Nickel Contact Dermatitis from Necklace Picture
- Nickel Contact Dermatitis Picture
- Photoallergic Reaction Picture
- Phototoxic Dermatitides Picture
- sinusitis sinus infection dos donts
- Slideshow 10 Common Allergy Triggers
- Slideshow 10 Worst Cities for Spring Allergies
- Slideshow Bad Bugs
- Slideshow Home Allergy Quiz
- Slideshow Nasal Allergy Relief
- Slideshow Nasal Irrigation
- Slideshow Pictures Common Food Allergy Triggers
- Slideshow Pictures Nasal Allergy Attack
- Slideshow Pictures Out of Control Allergies
- Slideshow Sinusitis
- treatment mold allergy symptoms
Allergies Quizzes
Allergies News
- 'Egg Therapy' May Help Allergic Kids
- AAP Updates Epinephrine Guides Use for Anaphylaxis
- Act Quickly to Beat Mold After a Flood
- Adverse Reactions to Antihistamines Are Common
- African-American Kids May Have More Food Allergies
- Allergy Prevalence the Same, Regardless of Area
- Allergy Relief Can Be Hard to Find
- Allergy Risk in Kids Linked to Low Vitamin D
- Allergy Self-Diagnosis Leads to Misdiagnosis
- Allergy Shots Cut Health Care Costs For Kids
- Allergy Tests and Food Diets: What Parents Need To Know
- Antibiotics Do Not Reduce Symptoms of Sinus Infection
- Babies Who Eat Peanuts Early May Avoid Allergy
- Benadryl Gel: Don't Swallow It
- Benefits of Peanut Allergy Prevention Strategy
- Bullied Over Food Allergies
- Carbon Dioxide Gas May Treat Nasal Allergies
- Cell Phone Shopping? You May Be Allergic to Some
- Do Harsh Winters Mean Worse Allergies?
- EpiPen Price Hikes: What to Know
- Farm Life Linked to Fewer Allergies, Less Asthma
- FDA Approves 'Dry' Nose Spray for Allergy
- FDA May Ban Powdered Medical Gloves
- Food Allergies Linked to Asthma Risk
- Food Allergies Linked to Pesticides
- Food Allergy Guidelines Out
- Food Allergy Reactions in Kids Undertreated
- Genetic Explanation for Frustrating Syndrome
- Get First Cat as Adult, Double Allergy Risk
- Global EpiPen Recall Now Includes U.S.
- Global Warming May Double Pollen by 2040
- Got Hay Fever? New Tablets vs. Allergy Shots
- Kids With Food Allergies May Need 2 EpiPens
- Little Insects, Big Allergic Reactions
- Low Folate May Be Linked to Allergies
- Nasacort Allergy Spray Can Go OTC, FDA Panel Says
- Over-the-Counter Flonase Allergy Relief Approved
- Peanut Protein in Dust May Raise Allergy Risk
- Pets, Dust May Worsen Ragweed Allergies
- Pork-Cat Syndrome an Under-Recognized Allergy
- Probiotics May Ease Hay Fever Symptoms
- Recall: Canned Pasta Shells and Spaghetti
- Recall: Tyson Foods Chicken Products
- Relieve Ragweed Allergies Without Shots
- Scientists Closer to Cat Allergy Cure
- Secondhand Smoke Linked to Chronic Sinusitis
- Shifting Temps May Prime You for Spring Allergies
- Sinus Infections Linked to Nasal Washing
- Skin Patch to Treat Peanut Allergy
- Spring Pollen Allergies
- Sublingual Immunotherapy Helps Dust Mite Allergy
- The 10 Worst Places for Fall Allergies in 2012
- The Rising Threat of Hidden Food Allergens
- The True Cost of EpiPen Coupons
- Worst Cities for Spring Allergies in 2012
- Xolair May Treat Milk Allergy in Kids