Placebo-Controlled Multi-Centre Double-Blind Trial for Adults With Extended-Release Methylphenidate for ADHD

Inclusion Criteria: * Patient treated as outpatient or inpatient * Patient has a good command of German * Score of 85 or greater in the IQ test (MWT-B) * Diagnosis of ADHD according to ADHD-CL (DSM IV) and WRI-WRAADDS \> 28 points * ADHD symptoms have existed since childhood (WURS-k \>= 30) * Body mass index \>= 20 * Willing to eat breakfast * Patient is willing and able to come to the observation appointments * Written consent of the patient to participate in the study Exclusion Criteria: * Treatment with psychostimulants in the past 2 weeks * Inconsistencies in the CAARS- S:L \>= 8 (Inconsistency Index) * Shift work or night work * Alcohol, medication or drug dependency in the past 6 months or manifest drug abuse * Diagnosis of a psychosis (SKID-I) * Epileptic attacks in the past * EEG results which suggest epilepsy * Clinically relevant liver disease * Clinically relevant hyperthyroidism (relevantly elevated TSH, T4) * Acute depressive episode according to ICD-10 F32.2 and ICD-10 32.3 (SKID-I) * Illnesses with schizophrenic symptoms (SKID-I) * Acute manic episode, bipolar disorder (SKID-I) * Diagnosis of a tic disorder * Acute anorexia * Acute prominent panic disorder and generalised anxiety (SKID-I) * Clinically relevant kidney disorders * Known high blood pressure * Known occlusive arterial disease * Known angina pectoris * Known coronary heart disease and state after myocardial infarction * Known tachycardial arrhythmias * Post-stroke status * Known elevated intra-occular pressure * Known enlarged prostates * Participation in a clinical study within the past 30 days * Participation in this study at an earlier point in time * Simultaneous participation in another clinical trial * Women of child-bearing age without adequate contraception * Patients with terminal illness (e.g. cancer) * Pregnancy (positive pregnancy test) or lactation period