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.
Beta Blockers, also known as beta-adrenergic blocking agents, work by blocking the neurotransmitter epinephrine (adrenaline). Blocking adrenaline slows down and reduces the force of heart muscle contraction resulting in decreased blood pressure. Beta blockers also increase the diameter of blood vessels resulting in increased blood flow. Historically, beta blockers have been prescribed to treat the somatic symptoms of anxiety (heart rate and tremors) but they are not very effective at treating the generalized anxiety, panic attacks or phobias. Lopressor and Inderal are some of the brand names with which you might be familiar.
Anxiety disorders reflect disorders that share a general feature of excessive fear (i.e. emotional response to perceived or real threat) and/or anxiety (i.e. anticipation of future threat) and demonstrate behavioral and functional disturbances as a result. Panic attacks are a feature that can occur in the context of many anxiety disorders and reflect a type of fear response.
Panic attacks cause a variety of distressing symptoms that can be terrifying for the individual experiencing the attack. Some people mistake panic attacks for heart attacks and many believe that they are dying. Others feel a mixture of self-doubt or impending doom. Some can also find the episodes extremely embarrassing and refrain from telling their friends, family, or a mental health professional.
Panic disorder affects 2-3% of people every year in the United States and Europe, with varying rates depending on race and ethnicity. On average, Native American Indian populations experience panic disorder at higher rates than non-Latino white Americans. In contrast, African Americans, Latinos, Caribbean Blacks, and Asian Americans all experience the disorder at lower rates than non-Latino white Americans. In addition, it has been well established than females are twice as likely to be diagnosed with panic disorder than males (Asnaani, Gutner, Hinton, & Hofmann, 2009; McLean, Asnaani, Litz, & Hofmann, 2011). A number of factors (e.g., biological influences, temperament, exposure to stressors and trauma, cognitive factors, and environmental factors) have been identified as possibly influencing sex differences in rates of panic disorder (McLean & Anderson, 2009). However, no one theory has been determined so the underlying reason for sex differences in rates of panic disorder remains unknown.
Anxiety attacks can last anywhere between a few moments to 30 or more minutes. It’s also common for subsequent anxiety attacks to follow, causing the overall anxiety attack experience to last much longer as one episode is followed by another. Even though anxiety attacks eventually end, it’s common for the symptoms and after effects of an anxiety attack to linger for hours or even days, depending upon the severity of the attack and the level of stress your body is under.
Panic attacks involve sudden feelings of terror that strike without warning. These episodes can occur at any time, even during sleep. People experiencing a panic attack may believe they are having a heart attack or they are dying or going crazy. The fear and terror that a person experiences during a panic attack are not in proportion to the true situation and may be unrelated to what is happening around them. Most people with panic attacks experience several of the following symptoms:
There are many highly effective treatment options available for anxiety and anxiety-related disorders. These treatments can be broadly categorized as: 1) Psychotherapy; 2) Medications; and 3) Complementary and Alternative Therapies. Patients diagnosed with anxiety can benefit from one or a combination of these various therapies. Discussions of emerging therapies and types of care providers are also included.
Social Anxiety Disorder;Fear of social situations in which the person is exposed to unfamiliar people or to possible scrutiny by others. The individual fears that he or she will act in a way (or show anxiety symptoms) that will be embarrassing and humiliating, often times leading to avoidance of social situations and severe distress when participation in social situations can't be avoided. 
Anxiety attack disorder generally starts with one unexplained attack that can include a number of intense anxiety attack symptoms, which causes the individual to become concerned. As other attacks occur, fear of having anxiety attacks, what they mean, what the associated symptoms mean, and where the attacks and symptoms may lead, increases. This escalation of fear is often the catalyst that brings on the attacks, causing the individual to be seemingly caught in a cycle of fear then panic, then more fear, then more panic, and so on.
Because involuntary panic attacks can be caused by other medical conditions, such as mitral valve prolapse, thyroid problems, hyperglycemia, side effects from certain types of medications, recreational drug use (such as marijuana), stimulants, etc., it’s best to discuss your panic attacks and symptoms with your doctor to rule out any medical cause.
Since anxiety disorders are a group of related conditions rather than a single disorder, they can look very different from person to person. One individual may suffer from intense anxiety attacks that strike without warning, while another gets panicky at the thought of mingling at a party. Someone else may struggle with a disabling fear of driving, or uncontrollable, intrusive thoughts. Yet another may live in a constant state of tension, worrying about anything and everything. But despite their different forms, all anxiety disorders illicit an intense fear or anxiety out of proportion to the situation at hand.
I have occasional panic attacks, typically around one or two of what I consider minor panic attacks per month. A minor panic attack is one that I catch and manage to head off before it grows full-blown. I just have so much experience having and handling panic attacks that I’ve learned the curb them…usually. Sometimes, my coping mechanisms don’t work and I’m left suffering a full-blown panic attack and, of course, they’re terrible. I’m always on the lookout for new and better coping mechanisms to minimize the chances of one slipping through like that.
Panic attacks are common among all anxiety disorders but what sets panic disorder apart is that panic attacks are unexpected and occur "out of the blue" without an obvious trigger (American Psychiatric Association, 2013; Craske & Barlow, 2007). These unexpected panic attacks must be associated with a significant change in behavior or be followed by at least one month of persistent worry about having another attack or about what will happen if you have another panic attack.
Although anxiety is often accompanied by physical symptoms, such as a racing heart or knots in your stomach, what differentiates a panic attack from other anxiety symptoms is the intensity and duration of the symptoms. Panic attacks typically reach their peak level of intensity in 10 minutes or less and then begin to subside. Due to the intensity of the symptoms and their tendency to mimic those of heart disease, thyroid problems, breathing disorders, and other illnesses, people with panic disorder often make many visits to emergency rooms or doctors' offices, convinced they have a life-threatening issue.
“I was under a lot of stress — starting a new business, working 16-hour days, a close friend was ill and dying, and on top of all that, I was doing a super heavy workout regimen at the gym with a trainer," Sideman says. "So it was a lot of physical stress, emotional stress, and a lot of financial stresses." He says he also can see roots of anxiety in his childhood and teen years as well as in other family members.
Most people have experienced fleeting symptoms associated with anxiety disorders at some point in their life. Such feelings — such as having a shortness of breath, feeling your heart pounding for no apparent reason, experiencing dizziness or tunnel vision — usually pass as quickly as they come and don’t readily return. But when they do return time and time again, that can be a sign that the fleeting feelings of anxiety have turned into an anxiety disorder.
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:
It is common for a person with one anxiety disorder to also have another anxiety disorder. Anxiety disorders are also frequently accompanied by depression or substance abuse. Anxiety disorders can coexist with physical health conditions as well. In such instances, these physical health conditions will also need to be treated. Before undergoing any treatment, it is important to have a thorough medical exam to rule out other possible causes.
Situationally predisposed panic attacks don’t always occur immediately upon exposure to a feared situation or cue, but the individual is more likely to experience an attack in such situations. For example, a person who has a fear of social situations but who does not experience a panic episode in every social situation, or who experiences a delayed attack after being in a social environment for an extended period of time.
Cognitive therapy and exposure therapy are two CBT methods that are often used, together or by themselves, to treat social anxiety disorder. Cognitive therapy focuses on identifying, challenging, and then neutralizing unhelpful or distorted thoughts underlying anxiety disorders. Exposure therapy focuses on confronting the fears underlying an anxiety disorder to help people engage in activities they have been avoiding. Exposure therapy is sometimes used along with relaxation exercises and/or imagery.