Allergy by definition is an over reaction of our body’s immune system to normally harmless substances and every individual have different reaction even on the same type of allergens. There are also some who quickly develop the symptoms even with a brief exposure to it. Just like what happened to our son a few days back, he immediately develops a pretty swollen upper lip after it touches with a fresh water fish. In times like this, it is always great to have an allergy relief medicine nearby.
And as a general rule, it is always best and appropriate to see a doctor if you experience an allergic reaction so you will be guided accordingly of the proper treatment and regimen especially if it develops into a life threatening conditions.