Can someone please explain to me what happens to the body if you get stung by a bee and you are allergic?

hmmm...short version: when something is introduced into your body that it producens allergens to, from that point on you are allergic to it. More than other substances, and some people have more severe reactions than others. Well your body as smart as it is, is also very stupid...when it comes in your body sends these little things to eat up all the little thingies that trigger the reaction, but in the process of eating it these little cells blow up and release HISTAMINE and cause inflammation...everywhere. Histamine is used to fight bad things, but unfortunately histamine kills you. thats why you swell up and the worst places are your throat/lungs so you end up not being able to breath. Then sometimes (in your husbands case) I would assume it was so bad it caused his brain to go F*ing haywire possibly causing him to have a seizure. thats why anti-histamines are used when your sick...blocks the release of histamine because its stupid.

my brother turns blue in the face his throte swells up and he cant breath.he has to make sure there are shots around he has to inject if he ever gets stung

He had a classic allergic reaction. http://www.webmd.com/allergies/guide/anaphylaxis

under the skin, the child may have immediate reactions (those symptoms beginning within 4 hours), delayed reactions (symptoms that don't appear until more than four hours after the sting), or both. Classifying the reactions is important both for immediate management and for predicting future problems (Allergy Principles and Practice, Mosby 2003). Some immediate reactions are classified as local (a two - or three-inch area of swelling, redness and pain that lasts less than 24 hours). Others qualify as large local reactions (those that are larger -- often an entire limb -- or that last longer, but all symptoms are adjacent to stings). Systemic reactions are allergic responses distant from the sting and include symptoms such as hives, generalized itching, generalized swelling, low blood pressure, difficulty breathing, or anaphylactic shock -- a severe reaction involving most or all of these symptoms. A sting on the forehead with swelling of the eyelids is a large local reaction, while a sting on the foot with swelling of the eyelids is a systemic reaction. Large local reactions are rarely serious and rarely portend future severe allergies. Systemic allergic reactions, though, are present and future warning signs. A fourth type of immediate reaction is the toxic reaction, which can follow multiple stings. This is a direct result of bee venom, and not an allergic reaction. Symptoms can include fever, weakness, nausea, vomiting, and pain. Toxic reactions are rarely serious, but do sometimes sensitize the child and herald future allergic reactions. Delayed reactions result when the body's immune system prepares for future stings, but some of the exuberant defense measures inadvertently turn against the body itself. These symptoms begin more than four hours after the initial sting. Delayed reactions include serum sickness (fever, weakness, rash, swelling, and/or intense itching which begin a week after the sting), nephrotic syndrome (inflammation of the kidney), neuritis (inflammation of the nerves), or inflammation of other parts of the body.