By Adrian Sparrow
NeuLine Health

Allergies happen when your body reacts to a foreign substance. Your immune system creates antibodies in response to these otherwise harmless substances, and you may experience a variety of symptoms as your body attempts to neutralize the threat. 

There are several types of allergies: 

  • Food
  • Medicine
  • Insects
  • Seasonal
  • Eczema

Symptoms depend on the type of allergy, though itching and swelling are the most common.

Food allergies can cause tingling and swelling in the mouth, face, and throat; hives, and anaphylaxis. Nine of the most common allergens are dairy, eggs, peanuts, tree nuts, fish, shellfish, wheat, soy, and sesame. About 32 million people have food allergies in the US. 

Severe drug reactions affect roughly 10 percent of the world’s population. Symptoms include hives, itchy skin, rash, facial swelling, wheezing, and anaphylaxis. The most common trigger is penicillin, an antibiotic used for many infections. 

The most common source of insect allergies is bee and wasp stings and poisonous ant bites. Cockroaches and dust mites can also cause symptoms of nose or skin allergies. Insect allergies affect 5 percent of the population. Symptoms include itching and hives all over the body, cough, tightness in the chest, wheezing or shortness of breath, a large area of swelling at the site, and anaphylaxis. 

Seasonal allergies can be caused by pollen and mold spores and may occur alongside asthma. People with seasonal allergies are likely to be allergic to multiple triggers. This kind of allergy tends to run in families. Symptoms include sneezing, an itchy nose, eyes, and roof of the mouth; a runny or stuffy nose; and watery red or swollen eyes. As the name says, these allergies tend to only last during a specific season while the offending pollen is most active. 

Eczema, also known as atopic dermatitis, is when the skin overreacts to minor irritants and allergens. As many as 15 million Americans have this condition. Plants such as poison ivy, poison oak, and poison sumac are the most common skin allergy triggers outside of chronic eczema, alongside pet dander and latex. Symptoms include red, itchy, or peeling skin. 

Anaphylaxis is a severe reaction to allergens that can cause you to go into shock. Symptoms of this life-threatening reaction can include loss of consciousness, a drop in blood pressure, severe shortness of breath, skin rash, a rapid, weak pulse, nausea, vomiting, and lightheadedness. This condition requires emergency medical attention and a shot from an epinephrine auto-injector (such as EpiPen), if available. 

Preventing allergic reactions usually comes down to avoiding the known triggers, even if you take medication for it. Those with severe allergies may wear a medical bracelet if a reaction leaves them unable to communicate. It can be helpful to keep a diary of activities, food, symptoms, and what helps to ease the reaction in order to determine new allergy triggers.