The answer is no- anxiety can't kill you. But anxiety can mimic medical problems that can be life threatening, such as heart attacks and asthma attacks. So if you have asthma and heart problems, you need to be able to discern what is from a medical problem, and what is anxiety, as these medical conditions can kill you if they are untreated. Click here for more information on the difference between a heart attack and panic attack, and click here for more information on the difference between an asthma attack and panic attack.