Overview Observational Study to Assess the Frequency of Lidocaine Ineffectiveness in Hard-to-treat ADHD Status: Completed Trial end date: 2020-03-30 Target enrollment: Participant gender: Summary This work will assess the prevalence in hard-to-treat ADHD of the ineffectiveness of the anesthetic Lidocaine. Phase: Early Phase 1 Details Lead Sponsor: PhenoSolve, LLCCollaborators: Boston Clinical TrialsNeurAbilities (formerly CRCNJ)Treatments: Lidocaine