Opioid Drug Interaction Study

Inclusion Criteria:

* English-speaking and literate participants, able to understand and sign Informed Consent Document
* ages 18 to 55 years old inclusive
* BMI of greater than/equal to 17 and approximately less than or equal to 30
* self-reported opioid use
* self-reported sedative-like drug use
* women of childbearing potential must not be pregnant or breastfeeding at screening and be using an effective form of contraception throughout study participation
* otherwise healthy as determined by the medical/research team based on medical history, physical examination, vital signs, laboratory chemistries (blood chemistry with liver function tests and hematology, urinalysis and microscopic evaluation, 12-lead electrocardiogram)
* willing and able to comply with all testing requirements defined in the protocol
* adequate venous access (determined by RN) for pharmacokinetic blood draws

Exclusion Criteria:

* physical dependence on alcohol, opioids, benzodiazepines or sedative/hypnotics requiring medical management/detoxification
* seeking treatment for opioid or any other drug use
* acute medical problem (e.g., infection) or chronic medical problem requiring daily medication or ongoing medical care (e.g., hypertension, cardiovascular disease, diabetes, respiratory disorders \[e.g., asthma, COPD\])
* clinically significant abnormal ECG (as determined by study physician/cardiologist)
* clinically significant abnormal laboratory findings (e.g., liver function tests greater than 3x the upper limits of normal range)
* current or past history of major psychiatric disorder that would limit ability to participate in the study (e.g., bipolar disorder).
* recent use of CYP2C9, CYP2D6 and CYP3A4 inhibitor or inducer that is long-acting and not amenable to a wash-out period after enrollment
* known hypersensitivity to any of the study drugs
* currently pregnant or breastfeeding
* currently under parole or probation with urine testing requirements