Fear.

Fear is a negative emotion that occurs when (real, illusory, alleged) threat to the life, health, well-being its and/or emotionally significant people and/or objects (even a pet).
If you encounter fear includes biochemical reactions, namely the release of adrenaline. It is also called the hormone of fear.
When adrenaline is included the behavioral response, often called the "fight or flight", that is, the behavior for a more or less successful protection from danger. The release of adrenaline leads to increased and rapid heart beat to improve blood supply to muscles and other organs that are important in the performance of the reaction "fight or flight", increased blood pressure with the same purpose; constriction of superficial capillaries (small blood vessels), which leads to cold extremities, pallor to reduce blood loss at the wound surface; the relaxation of the muscles of the bowel to release gut contents, and the contraction of the muscles of the stomach and esophagus are also to be exempt from the content to protect against contact with the contents of the stomach and intestine into the surrounding tissue with a deep abdominal wound. Thus the fear and adrenaline effect runs the instinct of self-preservation. Therefore, it is the right thing when the real threat.
BUT. But there is an illusory, imaginary fears, panic attacks. Biochemical principle is the same. But there is no defense, except for the painful unpleasant frightening feelings that negatively affect quality of life, namely the narrowing of personal freedom of behavior, communication, movement and so on. Illusory, imaginary fears, panic attacks — a kind prints long-deferred and forgotten the real threats or false mask, under which hides the true consciousness of the threat but which are not currently able to receive and not able to create an effective defense against it. And almost all of my clients are saying about their complaints, while their minds are securely hides the true cause. It's like to talk in detail about what the branches of the tree, what fruit and absolutely to exclude, what his roots...the roots are hidden under a thick layer of the earth...causes hidden under a thick layer of consciousness.
Yes, the medication improve physical condition, but the desired result is the complete liberation of neurotic fears possible with mandatory psychotherapy.