Stress and drug abuse: the brain connection.

You are about to take a test. The coach is announcing who made the team. Your best friend is mad at you. Most people find such situations stressful. Stress can be defined as an emotional or physical demand or strain (a "stressor") that causes your body to release powerful neurochemicals and hormones. These changes help your body gear up to respond to the stressor. Your blood-sugar levels and blood pressure rise; your heart beats faster; your muscles tense.

There are different levels of stress: Short-term stress can cause uncomfortable physical reactions, but can also help you to focus. Long-term stress--such as stress caused by illness, divorce, or the death of a loved one--can lead to serious health problems. Traumatic events--such as natural disasters, violence, and terrorism--can cause post-traumatic stress disorder (PTSD), a serious illness.

Brain research now indicates that people exposed to stress are more likely to abuse alcohol or other drugs, or to relapse to drug addiction.

Read on to get important facts about this connection.