The effects of having a panic attack or anxiety attack are:
   Generally  there  is  a  prolonged  state  of  tension, there  may  be  feelings  of nervousness, impatience and irritability. You  may  find  there is  an  increase  in  fear, increased  tension  whenever you experience  anything that reminds you of 
the  original  panic. In  generating  avoidance of the original 'Cause', you can be- come  more restricted in  your lifestyle, perhaps developing phobias of one type
or other. Depression,  lack  of  self  confidence, increased  bad dreams and IBS, maybe other symptoms that develop  alongside.
There is a cause, one deep inside your mind, and once removed the symptoms disappear never to return

Repressed Emotion = Depression and Anxiety

The Treatment. If repressed  emotion  is  the  cause, then  it would follow that if we release the repressed emotion then the depression and anxiety will be removed as well. Unfortunately someone suffering with depression or anxiety can't remember consciously what it is upsetting them, but their subconscious knows exactly what memories are still upsetting them, so with the help of hypnosis we ask it. 
Hypno-Analysis. Combines Psychotherapy and Hypnosis and is used to discover the original cause of psychological problems. Every effect (your symptoms) must have a cause; once this cause is revealed, it is removed, bringing consequent relief from the symptoms.
Combining psychotherapy with hypnosis: rapid results can be achieved in a few weeks, usually 6 to 12 sessions, depending on the severity of the symptoms. The therapy allows us to ask the subconscious mind what is troubling it and it starts to recall all the memories that are the cause of the depression and anxiety. 
As the memories are recalled all the emotion connected to those memories is released.

You don't have to put up with psychological or emotional issues,  you can regain control of your life with; 
 Hypnotherapy or Hypno-analysis

Effects of a panic attack?
   Because  of  the  adrenalin  response  many different physical and emotional reactions can occur:  Breathing  may be rapid, there may be difficulties in  breathing, the heart beat may be rapid  with  pains  in  the  chest. You  may  feel dizzy,  hot  or  cold, nauseous,  an  increase in sweating. You  may  experience  Tinitus; there may be a numbness or a tingling in the extrem- ities. Fear and Panic, a sense of unreality may be  experienced  making  you  feel  detached from  your  body  or  surroundings leaving them feel  unsteady  and  shaken. Panic attacks vary in  length  or  duration even frequency, however they  leave  you  feeling  anxious  because  you never know when the next attack will be