Maybe you've heard of drugs called heroin, morphine or codeine. These are examples of opiates. If someone uses opiates again and again, his or her brain is likely to become dependent on them. PDF for Mind Over Matter - Opiates [PDF - 775 KB] The Brain's Response to Opiates How Do Opiates Work? How Does Someone Become Addicted to Opiates? Surprising Facts The Search Continues The Brain's Response to Opiates › Español