Orexin Receptor Antagonism and Sleep in Stimulant Use Disorder

Inclusion Criteria:

* Meet Diagnostic and Statistical Manual of Mental Disorders(DSM-5)criteria for primary stimulant use disorder (either cocaine or methamphetamine)
* Be fluent in English and able to understand the consent form

Exclusion Criteria:

* Have an opioid use disorder of any severity
* Have a greater than moderate substance use disorder on any other substance
* Undergoing medication-assisted treatment for withdrawal of any substance
* Have any medical conditions contraindicating SUVO (e.g., severe pulmonary disease, severe cardiovascular disease or clinically abnormal ECG, severe liver or kidney disease, seizure disorder, or sleep disorder -particularly narcolepsy)
* Are currently taking medications with known drug interactions with SUVO (e.g., Monoamine oxidase (MAO) inhibitors, anticonvulsants, haloperidol, phenothiazines, anesthetics, and any sedative)
* Are pregnant or breast feeding
* BMI \> 30 (women only)
* Have a current DSM-5 psychiatric disorder or neurological disease requiring on-going treatment that would make participation unsafe
* Have history of seizure disorder
* Have a head injury with loss of consciousness in the last 5 years