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Allergic Reaction Topic Guide

Allergic Reaction Allergic Reaction: An allergic reaction is an overreaction to a harmless substance. Symptoms and signs of an allergic reaction include hives, rashes, swelling, itching, wheezing, nausea, and even anaphylactic shock in severe reactions. Treatment involves avoiding triggers, taking oral antihistamines, applying anti-inflammatory steroid creams, and using an EpiPen.
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Hives and Angioedema
Hives and Angioedema Hives are a sudden allergic skin reaction. Hives are raised reddish bumps that cause severe itching. Angioedema is similar to hives but the welts are larger and involve a deeper layer in the skin. Allergies, insect stings and bites, stress, exercise, and infections are common causes of hives and angioedema. In mild cases, no treatment is needed. Severe reactions should be treated by a health care professional.

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Allergic Reaction Topic Guide - Medications and Vitamins

Medications:

epinastine ophthalmic Epinastine Ophthalmic

Epinastine is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, wate...learn more »

desloratadine Desloratadine

Desloratadine is an antihistamine that is used to treat the symptoms of allergies, such as sneezing, watery eyes, itching, and runny nose.

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flunisolide nasal Flunisolide Nasal

Flunisolide is a steroid. It prevents the release of substances in the body that cause inflammation...learn more »

fexofenadine and pseudoephedrine Fexofenadine And Pseudoephedrine

Fexofenadine is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, wa...learn more »

triamcinolone (nasal) Triamcinolone (nasal)

Triamcinolone is a steroid that prevents the release of substances in the body that cause inflammation...learn more »

fexofenadine Fexofenadine

Fexofenadine is an antihistamine that is used to treat the symptoms of seasonal allergies (hay fever) in adults and children...learn more »

cetirizine Cetirizine

Cetirizine is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, wate...learn more »

hydroxyzine Hydroxyzine

Hydroxyzine reduces activity in the central nervous system. It also acts as an antihistamine that reduces the effects of natural chemical histamine in the b...learn more »

cyproheptadine Cyproheptadine

Cyproheptadine is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, ...learn more »

promethazine (injection) Promethazine (injection)

Promethazine is in a group of drugs called phenothiazines (FEEN-oh-THYE-a-zeens). It works by changing the actions of chemicals in your brain.

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promethazine (rectal) Promethazine (rectal)

Promethazine is in a group of drugs called phenothiazines (FEEN-oh-THYE-a-zeens). It works by changing the actions of chemicals in your brain. Promethazine...learn more »

promethazine (oral) Promethazine (oral)

Promethazine is in a group of drugs called phenothiazines (FEEN-oh-THYE-a-zeens). It works by changing the actions of chemicals in your brain. Promethazine...learn more »

cromolyn sodium (ophthalmic) Cromolyn Sodium (ophthalmic)

Cromolyn sodium works by preventing the release of substances in the body that cause inflammation...learn more »

epinephrine injection Epinephrine Injection

Epinephrine is a chemical that narrows blood vessels and opens airways in the lungs. These effects can reverse severe low blood pressure, wheezing, severe s...learn more »

prednisone Prednisone

Prednisone is a steroid that reduces inflammation in the body, and also suppresses your immune system...learn more »

diphenhydramine Diphenhydramine

Diphenhydramine is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching,...learn more »

cromolyn sodium (oral) Cromolyn Sodium (oral)

Cromolyn sodium works by preventing the release of substances in the body that cause inflammation...learn more »

cromolyn sodium (inhalation) Cromolyn Sodium (inhalation)

Cromolyn sodium works by preventing the release of substances in the body that cause inflammation...learn more »