Panic attacks are very sudden, discrete periods of intense anxiety, mounting physiological arousal, fear, stomach problems and discomfort that are associated with a variety of somatic and cognitive symptoms. The onset of these episodes is typically abrupt, and may have no obvious triggers. Although these episodes may appear random, they are a subset of an evolutionary response commonly referred to as fight or flight that occur out of context. This response floods the body with hormones, particularly epinephrine (adrenaline), that aid it in defending against harm. Experiencing a panic attack is said to be one of the most intensely frightening, upsetting and uncomfortable experiences of a person’s life.