Opioid withdrawal symptoms are a major contributing factor for why opioid treatment programs often fail. Individuals with severe opioid withdrawal symptoms may experience shaking, muscle and bone pain, nausea, depression, anxiety, and drug craving. Tramadol is a medication that is currently used to treat moderate to severe pain in individuals with cancer, joint pain, or pain resulting from surgery. Because of its pharmacological profile, tramadol may also be useful in treating opioid withdrawal. Further research is needed to confirm the benefits of tramadol for opioid addicts. The purpose of this study is to evaluate the effectiveness of tramadol at reducing opioid withdrawal symptoms in opioid-dependent individuals.