Study to Confirm the AuthenTicity of Point of Care Urine samplEs Using Oral fluoreScein Sodium in adulTs With substancE Use Disorder (ATTESTED)

The purpose of this phase III, randomized, double-blind, placebo-controlled study is to confirm the authenticity of point-of-care urine samples in adult persons with substance use disorder using fluorescein sodium as a marker. Eligible persons will, drink a sample of Gatorade™ which includes either, 100 mg fluorescein sodium, or not, followed by 500 mL of water. Fifteen minutes after consuming the Gatorade™, participants will provide a mid-stream urine sample (at least 10 mL urine is required) for examination of fluorescence (in a single-blinded manner) using a Qubit™ fluorometer.