Will I get used to a cat allergy... Surprisingly the answer is... Yes. 

Cat allergies are caused by the proteins in a cat's urine and saliva. These proteins are also found in cat dander, dry flakes of skin found in the fur. If you are allergic to cats and decide to get one, then you'll be happy to learn most people tend to build up a tolerance to these allergens over time (it does take time). 

Source for more information: https://www.petmd.com/cat/care/evr_ct_cat_allergies

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