When a person injures themselves endorphins are released in the body and function as natural pain killers. The behavior may become addictive because the person learns to associate the act of self-injury with the positive feelings they get when endorphins are released in their system. The use of SSRI medications (selective serotonin reuptake inhibitors) such as Prozac and Zoloft, may be helpful in increasing brain serotonin levels and reducing self-injury in cases of moderate to severe... Sign in to see full entry.