Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Panic attacks are periods of intense fear or apprehension that are of sudden onset and of variable duration of minutes to hours. Panic attacks usually begin abruptly, may reach a peak within 10 minutes, but may continue for much longer if the sufferer had the attack triggered by a situation from which they are not able to escape. Learn more about panic attacks, their causes and treatment in this book.