Causes of Allergies

People who have allergies often are sensitive to more than one thing. Substances that often cause reactions are

Normally, your immune system fights germs. It is your body's defense system. In most allergic reactions, however, it is responding to a false alarm. Genes and the environment probably both play a role.

Source: MedLinePlus (NIH)1

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Back to: « Allergies

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The most common causes are reactions to foods (especially peanuts), medications, and stinging insects. Other causes include exercise and exposure to latex. Sometimes no cause can be found.

Source: MedLinePlus (NIH)2

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Your body’s immune system is a natural defence against infection and other foreign material. If you are allergic to something, your immune system will react every time you come into contact with that allergen.

Source: New Zealand Health3

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Causes of allergies

Many substances can cause an allergic reaction, but some of the most common are:

Source: New Zealand Health4

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Insect stings, drugs such as penicillin, and certain foods are some of the more common causes of severe allergic reactions.

Source: New Zealand Health5

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What causes allergies?

Allergies occur when the body's immune system reacts to a particular substance as though it's harmful.

It's not clear why this happens, but most people affected have a family history of allergies or have closely related conditions such as asthma or eczema.

The number of people with allergies is increasing every year. The reasons for this are not understood, but one of the main theories is it's the result of living in a cleaner, germ-free environment, which reduces the number of germs our immune system has to deal with.

It's thought this may cause it to overreact when it comes into contact with harmless substances.

Source: NHS Choices UK6

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Cladosporium: Cladosporium has also been associated with allergies and asthma.

Source: CDC7

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Mastocytosis: People with mastocytosis have an increased risk of developing a severe and life-threatening allergic reaction. This is known as anaphylaxis.

Source: NHS Choices UK8

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Mastocytosis: If you have systemic mastocytosis or extensive cutaneous mastocytosis, your risk of a severe allergic reaction (anaphylaxis) is increased.

Source: NHS Choices UK9

Causes of Allergies

Causes of the condition may include:10 Causes of Allergies:

Causes List for Allergies

Some of the possible causes of Allergies or similar disorders may include:11

... Full Causes List for Allergies »

Genetics of Allergies

Allergies run in families. Your children’s chances of developing allergies are higher if you have them. ...Source: NIH News in Health (NIH)12 ...

... More on Genetics »

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  1. Source: MedLinePlus (NIH): allergy.html
  2. Source: MedLinePlus (NIH): anaphylaxis.html
  3. Source: New Zealand Health: your-health/ conditions-and-treatments/ diseases-and-illnesses/ allergies
  4. ibid.
  5. ibid.
  6. Source: NHS Choices UK: conditions/ Allergies/ 
  7. Source: CDC: fungal/ diseases/ other/ index.html
  8. Source: NHS Choices UK: conditions/ Mastocytosis/ 
  9. Source: NHS Choices UK: conditions/ mastocytosis/ symptoms/ 
  10. Source: Human Phenotype Ontology
  11. Source: Algorithmically Generated List
  12. Source: NIH News in Health (NIH): issue/ jun2016/ feature2

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Note: This site is for informational purposes only and is not medical advice. See your doctor or other qualified medical professional for all your medical needs.