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.
If the person has a family history of seizures or symptoms that are not typical for panic attack, a neurologist may be asked to evaluate the person. There is some overlap between the symptoms of panic attack and what is known as "partial seizures." Distinguishing between the two is important because the treatment for each is quite different. A neurologist, if consulted, will order an EEG (electroencephalogram) to check for seizure activity in the brain. This is a painless test but does require some time to complete (typically overnight).
People with generalized anxiety disorder (GAD) display excessive anxiety or worry, most days for at least 6 months, about a number of things such as personal health, work, social interactions, and everyday routine life circumstances. The fear and anxiety can cause significant problems in areas of their life, such as social interactions, school, and work.