Moreover, this hypocapnia and release of adrenaline during a panic attack cause vasoconstriction resulting in slightly less blood flow to the head which causes dizziness and lightheadedness.[28][29] A panic attack can cause blood sugar to be drawn away from the brain and toward the major muscles. Neuroimaging suggests heightened activity in the amygdala, thalamus, hypothalamus, and brainstem regions including the periaqueductal gray, parabrachial nucleus, and Locus coeruleus.[30] In particular, the amygdala has been suggested to have a critical role.[31] The combination of high arousal in the amygdala and brainstem along with decreased blood flow and blood sugar in the brain can lead to dramatically decreased activity in the prefrontal cortex region of the brain.[32] There is evidence that having an anxiety disorder increases the risk of cardiovascular disease (CVD).[33] Those affected also have a reduction in heart rate variability.[33]
So I can tell you that panic attacks aren't dangerous, but I recognize that this is "easy for me to say". If you're having anxiety attacks, especially if they're a relatively new occurrence for you, you might not be able to believe this right now. That's entirely understandable when you feel that your life is threatened! You don't need to take anything here on faith. Instead, check it all out. Test everything I say against your own experience, as you work your way through this site.
Women are more than two times as likely as men to be diagnosed with an anxiety disorder. (6) It’s not clear why this is the case, but researchers have theorized that it may be due to a combination of social and biological factors. Scientists are still investigating the complex role that sex plays in brain chemistry, but some research suggests that in women, the amygdala, which is the part of the brain responsible for processing potential threats, may be more sensitive to negative stimuli and may hold on to the memory of it longer. (7) 
Although there are not specific causes for panic attacks in adults, teens, or children, like most other emotional symptoms, panic is understood to be the result of a combination of biological vulnerabilities, ways of thinking, and environmental factors like social stressors. According to one theory of panic disorder, the body's normal "alarm system," also described as the body's fight or flight system, the set of mental and physical mechanisms that allows a person to respond to a threat, tends to be triggered when there is no danger. Scientists don't know specifically why this happens or why some people are more susceptible to the problem than others. Panic disorder has been found to run in families, and this may mean that inheritance (genetics) plays a role in determining who will develop the condition. However, many people who have no family history of the disorder develop it. Studies differ as to whether drugs like marijuana or nutritional deficiencies like zinc or magnesium deficiencies may also be risk factors for developing panic disorder.

If you’ve ever experienced a sudden surge of overwhelming anxiety and fear then you’re familiar with the feeling of having a panic attack. Your heart pounds, you can’t breathe, and you may even feel like you’re dying or going crazy. Left untreated, panic attacks can lead to panic disorder and other problems. They may even cause you to withdraw from normal activities. But panic attacks can be cured and the sooner you seek help, the better. With the right treatment and self-help, you can reduce or eliminate the symptoms of panic, regain your confidence, and take back control of your life
For example, once you notice you are scaring yourself with anxious thinking, you can change your thinking to calming thoughts, which will stop stress responses and their physiological, psychological, and emotional effects. As you calm yourself down, your body will follow by stopping the flow of stress hormones. As stress hormones are used up or expelled, the sensations, symptoms, and feelings of panic will subside…in time.
Medication can be used to control or lessen symptoms related to panic disorder. It is most effective when combined with other treatments, such as the aforementioned cognitive behavioral therapy and exposure therapy. Medications used to treat panic attacks and panic disorder include antidepressants, though they take several weeks to reach effectiveness. Benzodiazepines such as Ativan and Xanax work quickly. However they are addictive and should only be used for a short time,
Post-traumatic stress disorder -- or PTSD -- was considered to be a type of anxiety disorder in earlier versions of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders. But in 2013, PTSD was reclassified as its own condition. It describes a range of emotional reactions caused by exposure to either death or near-death circumstances (such as fires, floods, earthquakes, shootings, assault, automobile accidents, or wars) or to events that threaten one's own or another person's physical well-being. The traumatic event is re-experienced with fear of feelings of helplessness or horror and may appear in thoughts and dreams. Common behaviors include the following:

Anxiety is a normal reaction to danger, the body’s automatic fight-or-flight response that is triggered when you feel threatened, under pressure, or are facing a stressful situation. In moderation, anxiety isn’t necessarily a bad thing. It can help you to stay alert and focused, spur you to action, and motivate you to solve problems. But when anxiety is constant or overwhelming—when it interferes with your relationships and daily activities—you’ve likely crossed the line from normal anxiety into the territory of an anxiety disorder.
Anxiety disorders are associated with chronic life stress. Unpredictable, unrelenting, unresolvable stressors chronically stimulate the stress hormone system and cardiovascular system, and lead to states of constant increased activity. Biologically, the body has evolved to deal with imminent and concrete danger in the environment, rather than continuous stressors. Under normal conditions where chronic stress is low, exposure to a sudden threat activates the autonomic nervous system, i.e. increased levels of adrenaline and faster breathing, and racing heart rate. These reactions in turn trigger activation of stress hormones, such as cortisol. One of the effects of these stress hormones is to increase glucose levels in the bloodstream in order to respond to the imminent threat, so that muscles can be activated for the flight or fight response. Another effect of stress hormones is to supress the immune system, since processes such as healing and repair can wait until after the threat subsides. However, in someone with an anxiety disorder, where there is constant activation of these responses to everyday stressors, the stress hormone system loses its ability to control immune function, thus contributing to heightened systemic inflammation that increases risk for cardiovascular and even autoimmune disorders. Neuroscience and clinical research continues to investigate how anxiety disorders increase individual risk for developing physical health co-morbidities in hopes of identifying new treatments that may alleviate suffering from and prevent the development of these whole-body disorders.

While obsessive-compulsive disorder is not officially classified by the American Psychological Association as an anxiety disorder, it shares many traits with common anxiety disorders, such as generalized anxiety disorder. In both conditions, you may know that your thoughts are irrational, but you feel unable to stop thinking them. Often, but not always, these thoughts may concern cleanliness, sex, or religion.

The disorder in younger children is less likely to have the symptoms that involve ways of thinking (cognitive symptoms). For example, panic attacks in children may result in the child's grades declining, decreased school attendance, and avoiding that and other separations from their parents. Both children and teens with panic disorder are further at risk for developing substance abuse and depression as well as suicidal thoughts, plans, and/or actions.
The degree of accompanying stress response and its physiological, psychological, and emotional changes are directly proportional to the degree of anxiety. For example, if you are only slightly concerned, such as being slightly nervous about meeting someone new, the body produces a small degree stress response. The small degree stress response can be so slight that you don’t even notice it.
The Diagnostic and Statistical Manual of Mental Disorders (DSM) is the handbook used for diagnosis of mental health disorders, and is widely used by health care professionals around the world. For each disorder, the DSM has a description of symptoms and other criteria to diagnose the disorder. The DSM is important, because it allows different clinicians and/or researchers to use the same language when discussing mental health disorders. The first DSM was published in 1952 and has been updated several times after new research and knowledge became available. In 2013, the most recent version of the DSM, the DSM-5, was released. There are a few important differences with its predecessor DSM-IV regarding anxiety disorders. First, Obsessive Compulsive Disorder (OCD) is not part of the anxiety disorders any more, but now has its own category: Obsessive-Compulsive, Stereotypic and related disorders. Second, Post-Traumatic Stress Disorder (PTSD) now also has its own category: Trauma and Stressor-related Disorders.
Anxiety attacks, also called panic attacks, are episodes of intense fear and emotional distress that usually occur suddenly and without warning, and typically last from several minutes up to an hour. These attacks may have a discrete trigger, but they also can occur without any identifiable cause. Anxiety attacks are often recurrent, and are very distressing to the people who experience them, as well as their loved ones.

For more information, please visit Mental Health Medications Health Topic webpage. Please note that any information on this website regarding medications is provided for educational purposes only and may be outdated. Diagnosis and treatment decisions should be made in consultation with your doctor. Information about medications changes frequently. Please visit the U.S. Food and Drug Administration website for the latest information on warnings, patient medication guides, or newly approved medications.
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