The term reaction has many different definitions when it comes in context with different words. Like there are chemical reactions, drug reactions, allergy reactions, etc. reaction is a way of giving response or acting against or opposing. Some define it as a response that depicts feelings of a person or attitude of a person and many more definitions from different people depending on their thinking.

A chemical reaction is a method in which one group of chemical substance is transformed into another group. It can also be taken as a procedure in which a substance is transformed into a new substance with different properties. A chemical reaction occurs when bonds between the molecules are either destroyed or created. The possible number of chemical reactions present in the nature is very massive, since there are many different types of molecules.

Synthesis is a type of chemical reaction, wherein two or more molecules combine to form a new molecule. For example, when iron is combined with oxygen it forms iron oxide, which is also known in general terms as rust. Analysis is opposite to synthesis, also known by the name chemical decomposition. Here the molecule breaks into its constituent molecules. When a more reactive molecule emits a part of another molecule and takes its place it is called substitution, another chemical reaction. When a substance is burnt involving oxygen and is destroyed, it is a combustion reaction.

An allergic reaction is the body’s way of responding to an aggressor. Immune system protects our body from harmful agents like toxins or bacteria. It activates when it feels the presence of foreign substance, antigen, in our body. When it over reacts to the non-toxic substance or allergen it becomes allergic reaction. Common allergens are dust, medications, certain foods, plants, pollens, viruses, insects or exposure to bright light. The reactions to these allergens come in the form of rashes, vomiting, fever, running nose, headache, itching eyes, etc. in some serious cases the person experiences asthma depending on the immune system of the their body.

Allergic reactions develop faster in some people and worsen their condition. Hence, medical attention should be taken as soon as possible even in the case of minor symptoms. If the treatment given does not work in few days of prescribed time, re consult your physician for more help. Discuss to them about your problem of reaction and give complete details of what was prescribed previously to guide them to treat you better in future.