Anaphylactic shock: what is it? Hypersensitivity at cellular level

Our body is programmed to reject the foreign material entering our system. As our body's defense mechanism produced antibodies to fight against the foreign substances. This is good when a foreign substance is harmful, such as certain bacteria or viruses. But some people's immune systems overreact to substances that are not harmful, and cause an allergic reaction to throw it out of our system, by producing a flood of chemicals to defend us. The word anaphylaxis, derived from the Greek, Ana meani...