Inclusion Criteria:  Participants aged at least 18 y/o diagnosed with ADHD by Diagnostic and Statistical Manual of Mental Disorders (DSM) Participants with a lower than 0 TOVA score or with a higher than 0 score whom as per investigator opinion suffer from ADHD Participants who experienced treatment failure with more than one ADHD conventional drug Participants willing to attend all the visits in the trial.  Exclusion Criteria:  Participants who were treated with benzodiazepines, antihistamines, etc, in the week that preceded the trial start. Participants suffering from neurologic or psychiatric diseases Participants suffering from malignant diseases Participants suffering from syndromes or metabolic diseases Participants with significant clinical diagnosis that can damage the trial unfolding. The investigator may include them after the end of the situation which prevented their previous inclusion. Participants breastfeeding, pregnant or not willing to use contraceptives. Participants that will not adhere to the protocol as per investigator opinion Participants who weight less than 45 kg or more than 120kg or with BMI greater than 30 Participants participating in another clinical trial which includes drug treatment Participants receiving any treatment for ADHD Participants using drugs Participants using cannabis or products containing cannabinoids, including medical cannabis.