Yes, it is possible to develop an allergy to something you weren't previously allergic to. Your body chemistry changes about every seven years making Allergies easy to develop.
Yes, people could develop an allergy to raccoons.
Anyone who has or is, developing an allergy, may need to get allergy shots. There are many ways one can develop an allergy: to outside or inside pollutants, allergic to dogs or cats, allergic to metals, etc. Usually one gets allergy shots when the allergic reaction is so bad and persistant, that they need to seek professional help.
yes you can develop an allergy or a sensitvity to anything at any time
I haven't eaten coconut for 7 years, and the other day I was by a coconut, and I started sneezing.
Well allergies can develop overtime. Often when someone suddenly becomes allergic to something new (particularly food) it is because they ate something that was off/bad and it made them slightly sick. So when you eat that same food the body rejects it, thus creating an allergy to that food.
Yes, there is a possibility that anyone at anytime can develop an allergy to marijuana.
Allergies can develop over time.
First, almost no one is allergic to pure gold. But pure gold is rare (too soft for jewelry) and you may be allergic to the alloying material. A dermatologist can test you, or you can acquire a pure gold ring and wear it for a week or two: if you don't develop a rash then you're not likely to be allergic.
An allergic response is the body's way of recognizing a harmful substance. Sometimes this mechanism becomes hypersensitive and reacts to things that are not harmful. That is what is most commonly referred to as an allergy. For example, some people are allergic to metals like the ones in jewelry and develop a green discoloration in their skin. This tends to happen to rings on some people's fingers.
Allergies develop when the body overreacts to an antigen.
No, swine flu is a virus and must be caught from someone or something which is carrying it. It does not just spontaneously materialise in a body.
Yes, that is how most people get it. Just 80% of people who have pollen allergy develops allergic asthma. It's not as bad as the one you are born with but it can develop into it. I got my asthma after I had my second child. But I also have a severe allergy against pollen and fur.