This is a human laboratory systematic examination of whether adding the FDA-approved gabapentin (Neurontin; oral) to the FDA-approved opioid hydromorphone (Dilaudid; oral) will 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 chronic lower back pain and no history of substance use disorder. Study subjects and staff are blinded to the study drugs and the class of drugs under investigation and are informed that subjects may receive opioids, stimulants, gabapentinoids, cannabinoids, benzodiazepines, over the counter medications, and/or placebo. Sessions last up to 8-hours in an outpatient setting. Primary outcomes are collected from participants prior to dosing and at several hour periods post-dosing.
