Overview

The purpose of this study is to assess the effects of transcranial Direct Current Stimulation (tDCS) applied in conjunction with Transcranial Ultrasound (TUS) for the treatment of addiction in opiate use disorder with chronic pain. The investigators hypothesize that there will be a decrease in drug use and improved psychosocial assessments with active stimulation, when compared to sham stimulation.

Eligibility

Inclusion Criteria:

1. Providing informed consent to participate in the study.
2. 18 to 85 years old.
3. Having a diagnosis of OUD, in the setting of CP:
   • OUD of more than 6 months duration as defined by Diagnostic and Statistical Manual of Mental Disorders (DSM-5) [64] and a positive urine toxicology screen.
   • or OUD patients who still feel craving or have not received more than 60 mg of methadone/day from the Methadone program.
4. Lives in the immediate area with no plans to relocate

Exclusion Criteria:

1. The subject is pregnant.
2. Recently started on antiepileptic drug therapy.
3. History of illegal stimulant use as demonstrated by urine toxicology.
4. . Ingestion of poppy seeds or herbal teas containing Papaveris Fructus (may cause a positive opiate test for morphine, codeine [66, 67]).
5. History of neurological disorders involving stroke, brain tumors, or epilepsy as self- reported (note patients will also be evaluated via electroencephalography (EEG) at baseline 1 week prior to stimulation and any patient showing abnormal EEG activity will be removed)).
6. History of unexplained fainting spells as self-reported.
7. History of head injury resulting in more than a momentary loss of consciousness as self-reported.
8. History of brain surgery as self-reported.
9. Contraindications to tDCS applied in conjunction with TUS:
   • Metal in the head, or
   • Implanted brain medical devices.
10. Suffering from severe depression (with a score of >30 in the Beck Depression

    Inventory (BDI), PHQ-9≥10).

11. Active malignancy.
12. History of suicidal behavior or suicide attempts.