Substance use treatment; Detoxification; Outpatient; Residential/24-hour residential; Outpatient detoxification; Outpatient day treatment or partial hospitalization; Intensive outpatient treatment; Outpatient methadone/buprenorphine or naltrexone treatment; Regular outpatient treatment; Residential detoxification; Naltrexone used in Treatment; Does not treat alcohol use disorder; Prescribes naltrexone; Naltrexone (oral); Naltrexone (extended-release, injectable); Private for-profit organization; State department of health; Cash or self-payment; Young adults; Adult women; Adult men; Opioids detoxification; Medication routinely used during detoxification; Smoking not permitted; Adults; Young adults; Female; Male; Opioid use disorder clients only; Vaping not permitted