This is a single-group, within-subject, double-blind, double-dummy, placebo and active-controlled study evaluated whether the FDA-approved cannabinoid dronabinol (Marinol) would enhance analgesia, subjective reports, and cognitive performance when compared to the FDA-approved opioid hydromorphone (Dilaudid).

This was a human laboratory systematic examination of whether adding the FDA-approved cannabinoid dronabinol (Marinol; oral) to the FDA-approved opioid hydromorphone (Dilaudid; oral) would change the experience of hydromorphone as rated by laboratory measures of pain, subjective reports of drug effects, and cognitive performance. Subjects are healthy individuals with no history of drug use disorder. Study subjects and staff were completed blinded to the study drugs and the class of drugs under investigation and were informed that subjects may receive opioids, stimulants, cannabinoids, benzodiazepines, over the counter medications, and/or placebo. All participants completed all sessions. Sessions lasted up to 8-hours and were conducted at least 7 days apart on an outpatient basis. Primary outcomes were collected from participants prior to dosing and at several hour periods post-dosing.

Inclusion Criteria:

• Aged 18-75
• Urine sample tests negative for common illicit substances of abuse, including cannabis
• Medically cleared to take study medications
• Are not pregnant or breast feeding
• Willing to comply with the study protocol.

Exclusion Criteria:

• Meet DSM-5 criteria for alcohol/substance use disorder
• Taking opioids for pain
• Previous adverse reaction to a cannabinoid product
• Prescribed and taking stimulants or benzodiazepines
• Answer "yes" to item 1 of the Brief Pain Inventory indicating chronic pain
• Self-report any illicit drug use in the past 7 days
• Presence of any clinically significant medical/psychiatric illness judged by the investigators to put subject at elevated risk for experiencing an adverse event
• History of seizure disorder
• Have a known allergy to the study medications or sesame seed oil
• Taking medications contraindicated with hydromorphone or dronabinol
• Have a history of clinically significant cardiac arrhythmias or vasopastic disease
• Have an abnormal and clinically-significant ECG

Adverse events were documented throughout each of the 5 outpatient, 8-hour sessions, up to 40 hours.

Adverse events were prompted systematically each hour throughout the session and documented according to good clinical practices. Spontaneously reported adverse events were also documented. All reports of symptoms were categorized as discrete events, such that one experience that included more than 1 symptom would be represented by more than 1 event. Events reported here were all rated as definitely or possibly related to study medication, collapsed across severity (mild, moderate, or severe).