Comparing Rapid Micro-Induction and Standard Induction of Buprenorphine/Naloxone for Treatment of Opioid Use Disorder

Inclusion Criteria: 1. Opioid Use Disorder (OUD) as defined by the Diagnostic and Statistical Manual of Mental Disorders-5 diagnostic criteria; 2. Individuals seeking Opioid Agonist Treatment (OAT); 3. Be 19 years of age or older; 4. Be willing and able to adhere to the study protocol and follow-up schedule; 5. Be able to provide written informed consent to participate in the clinical trial. 6. If female and of childbearing potential, agree to use an effective method of birth control approved by the study investigators throughout the study. Exclusion Criteria: 1. Diagnosis of severe medical or psychiatric conditions contraindicated for buprenorphine/naloxone or hydromorphone treatment; 2. Anticipated deterioration of health due to discontinuation of medications that are contraindicated with buprenorphine/naloxone and/or hydromorphone; 3. Positive pregnancy test for women of childbearing potential; 4. Methadone use in the past 5 days; 5. Buprenorphine use in the past 5 days; 6. Known allergy or sensitivity to buprenorphine/naloxone and/or hydromorphone; 7. Anticipation that the patient may need to initiate pharmacological treatment during the trial that is deemed unsafe by the study physician or could prevent study completion; 8. Unwilling or unable to use an effective method of birth control approved by the study investigators throughout the study.