By Colin Gilbert Post-Traumatic Stress Disorder (PTSD) is an anxiety disorder that results from a person\u2019s exposure to a terrifying event. Military combat, car accidents, or other near-death experiences are often at the root of the PTSD, which manifests itself in nightmares, cold detachment, or intense flashbacks. Traditional forms of therapy have long been considered the best option for helping people cope with the disorder. Now, however, the medical community has found a surprising new ally in the battle against PTSD. Beta blockers, which are usually used to treat high blood pressure and other heart conditions, are helping some people stop traumatic memories before they start. One beta blocker in particular, Propranolol, has been shown to interfere with the formation of traumatic memories. In 2003, the scientific journal Biological Psychiatry featured an article with a title that speaks for itself: \u201cImmediate treatment with Propranolol decreases PTSD two months after trauma.\u201d As the title implies, the beta blocker showed signs of effectiveness when given to people within just a few days of the traumatic event. In studies where some traumatized patients received the drug and others received an inactive placebo, the people who received the drug exhibited fewer signs of PTSD in the months that followed. However, the data is still inconclusive. While some studies suggest a link between beta blockers and the prevention of PTSD, others don\u2019t. Once PTSD has already established itself as a menacing force in a person\u2019s life, beta blockers like Propranolol don\u2019t seem to do much good. The reason for this seems to stem from the way traumatic memories are formed in the brain. During a frightening experience, the body\u2019s sympathetic nervous system enters a \u201cfight-or-flight\u201d mode, releasing stress hormones that raise blood pressure, sharpen the senses, and produce an acute sense of awareness. Immediately after the traumatic event, the hormones also affect the formation of the memory, eventually scarring the mind with a nightmarish series of associations. PTSD occurs when the memory of the event has become a permanent trigger for the intense panicked reaction. Beta blockers function by blocking the very stress hormones that are released during a terrifying experience, so they may also interfere with the subsequent production of traumatic memories. The less frightful a person is during and after an experience, the less likely he or she is to develop PTSD. Although many people are excited by the idea of preventing PTSD with beta blockers, others are more wary of the practical and ethical implications of deleting trauma. These critics believe that stripping a memory of psychological or emotional content is unwise and that the body\u2019s natural mechanisms for interpreting horrific events should be trusted. In a 2005 issue of Nature magazine, psychiatrist Dr. Paul McHugh asserted in response to the research on beta blockers and PTSD that "psychiatrists are once again marching where angels fear to tread." McHugh suggested that traumatic memories prevent people from experiencing the same kinds of horror in the future, but his opponents maintain that PTSD\u2019s disabling characteristics go beyond the scope the healthy coping mechanisms.