Drug addiction, also known as substance abuse disorder, is a very serious disease that affects people of all ages around the world. When a person is addicted to a drug, they have an uncontrollable craving for the drug because it becomes the only thing that makes them feel good. Without it, they feel anxious, sad, irritable and physically sick. They may no longer feel happy doing fun activities, like spending time with friends, exercising, watching a good movie, listening to music or eating their favorite foods. People with drug addiction often withdraw from friends and family and become obsessed with taking more and more of the drug.

Drugs can cause addiction because they rewire the brain to change a person’s behavior. Normally, when you do things like exercise, meditate or laugh, the brain releases chemicals called endorphins and neurotransmitters that cause you to be happy and feel less pain. This “natural high” is why many of us enjoy doing these healthy activities. When someone takes a drug like cocaine or opioids, it releases the same “feel good” chemicals, but in very large amounts. This causes the person to want to take more and more of the drug because of they feel so great afterward.

However, after repeated use of the drug, the high levels of the chemicals in the brain damage the part of the brain called the “reward center.” This part of the brain is very important in helping us remember good experiences. Once drugs rewire the reward center, a person no longer enjoys doing the things that they use to love, and they depend solely on the drug to get that euphoric feeling. Over time, someone with drug addiction will have trouble making decisions, solving problems and maintaining regular sleep patterns because drugs damage many other parts of the brain.

Doctors have a very difficult time treating drug addiction because the damage caused by drugs is very widespread in the brain. For this reason, doctors and scientists are always looking for new and better ways to help cure drug addiction. Scientists may have found a way to combat drug addiction by sending electrical currents to the brain. This treatment—called transcranial magnetic stimulation (TMS)—applies an electrical current to the outside of the head. The current stimulates the brain but is weak enough that it does not cause any physical damage. Using TMS, scientists have found they can greatly reduce a person’s craving for cocaine, heroin and alcohol. This treatment is very new and will need additional tests to see if it really works in a large number of people with drug addiction.

Although there is no cure for drug addiction just yet, the more we understand about how drugs damage the brain, the closer we can get to helping people with substance abuse disorder.