It is not unusual to experience only one or two symptoms at a time, such as vibrations in their legs, shortness of breath, or an intense wave of heat traveling up their bodies, which is not similar to hot flashes due to estrogen shortage. Some symptoms, such as vibrations in the legs, are sufficiently different from any normal sensation that they clearly indicate panic disorder. Other symptoms on the list can occur in people who may or may not have panic disorder. Panic disorder does not require four or more symptoms to all be present at the same time. Causeless panic and racing heartbeat are sufficient to indicate a panic attack.
Some of these symptoms will most likely be present in a panic attack. The attacks can be so disabling that the person is unable to express to others what is happening to them. A doctor might also note various signs of panic: The person may appear to be very afraid or shaky or be hyperventilating (deep, rapid breathing that causes dizziness). Anxiety attacks that take place while sleeping, also called nocturnal panic attacks, occur less often than do panic attacks during the daytime, but affect a large percentage of people who suffer from daytime panic attacks. Individuals with nocturnal panic attacks tend to have more respiratory symptoms associated with panic and have more symptoms of depression and of other psychiatric disorders compared to people who do not have panic attacks at night. Nocturnal panic attacks tend to result in sufferers waking suddenly from sleep in a state of sudden fright or dread for no known reason. As opposed to people with sleep apnea and other sleep disorders, sufferers of nocturnal panic can have all the other symptoms of a panic attack. Although nocturnal panic attacks usually last no more than 10 minutes, it can take much longer for the person to fully recover from the episode.
Generally, anxiety arises first, often during childhood. Evidence suggests that both biology and environment can contribute to the disorder. Some people may have a genetic predisposition to anxiety; however, even so, development of the condition is not inevitable. Early traumatic experiences can also reset the body’s normal fear-processing system so that it is hyper-reactive.
A person with separation anxiety disorder is excessively fearful or anxious about separation from those with whom he or she is attached. The feeling is beyond what is appropriate for the person’s age, persists (at least four weeks in children and six months in adults) and causes problems functioning. A person with separation anxiety disorder may be persistently worried about losing the person closest to him or her, may be reluctant or refuse to go out or sleep away from home or without that person, or may experience nightmares about separation. Physical symptoms of distress often develop in childhood, but symptoms can carry though adulthood.
People with panic disorder often worry about when the next attack will happen and actively try to prevent future attacks by avoiding places, situations, or behaviors they associate with panic attacks. Worry about panic attacks, and the effort spent trying to avoid attacks, cause significant problems in various areas of the person’s life, including the development of agoraphobia (see below).