A panic attack is a severe attack of anxiety and fear which occurs suddenly, often without warning, and for no apparent reason. In addition to the anxiety, various other symptoms may also occur during a panic attack. These include one or more of the following:
The physical symptoms that occur with panic attacks do not mean there is a physical problem with the heart, chest, etc. The symptoms mainly occur because of an overdrive of nervous impulses from the brain to various parts of the body during a panic attack. This overdrive of nervous impulses can lead to the body producing hormones which include adrenaline (epinephrine). This is sometimes referred to as a 'fight or flight' response. This kind of reaction is normal in people when we feel we are in danger. During a panic attack the body can react in the same way.
During a panic attack you tend to over-breathe (hyperventilate). If you over-breathe you blow out too much carbon dioxide which changes the acidity in the blood. This can then cause more symptoms such as confusion and cramps, and make palpitations, dizziness, and pins and needles worse. This can make the attack seem even more frightening, and make you over-breathe even more, and so on. It can sometimes result in a faint. A panic attack usually lasts 5-10 minutes, but sometimes they come in waves for up to two hours.