Allergy symptoms, which depend on the substance involved, can affect your airways, sinuses and nasal passages, skin, and digestive system. Allergic reactions can range from mild to severe. In some severe cases, allergies can trigger a life-threatening reaction known as anaphylaxis.
Hay fever, also called allergic rhinitis, can cause:
- Sneezing
- Itching of the nose, eyes or roof of the mouth
- Runny, stuffy nose
- Watery, red or swollen eyes (conjunctivitis)
A food allergy can cause:
- Tingling in the mouth
- Swelling of the lips, tongue, face or throat
- Hives
- Anaphylaxis
An insect sting allergy can cause:
- A large area of swelling (edema) at the sting site
- Itching or hives all over the body
- Cough, chest tightness, wheezing or shortness of breath
- Anaphylaxis
A drug allergy can cause:
- Hives
- Itchy skin
- Rash
- Facial swelling
- Wheezing
- Anaphylaxis
Atopic dermatitis, an allergic skin condition also called eczema, can cause skin to:
- Itch
- Redden
- Flake or peel
Anaphylaxis
Some types of allergies, including allergies to foods and insect stings, can trigger a severe reaction known as anaphylaxis. A life-threatening medical emergency, anaphylaxis can cause you to go into shock. Signs and symptoms of anaphylaxis include:
- Loss of consciousness
- A drop in blood pressure
- Severe shortness of breath
- Skin rash
- Lightheadedness
- A rapid, weak pulse
- Nausea and vomiting
It is important to note that not everyone who is allergic to a particular allergen will experience the same symptoms. Some people may only have mild symptoms, while others may have severe reactions that require medical attention.