Gross‐Tsur 2004.

Methods	A patient series of 3 children with ADHD who manifested hallucinations during methylphenidate treatment at low therapeutic doses
Participants	Diagnosis of ADHD: DSM‐IV‐TR (subtype: combined (33.3%), not stated (66.6%)) Age: 7, 12, 7½ years old IQ: > 70 Sex: male Ethnicity: not stated Country: Israel Comorbidity: ODD (33%), cerebral palsy (33%), mild learning disabilities (33%) Comedication: not stated Sociodemographics: adopted (33%)
Interventions	Methylphenidate type: not stated Methylphenidate dosage: 0.25‐0.3 mg/kg, 7.5‐10 mg Administration schedule: once daily Duration of treatment: 1 for a short period, 2 for several months/1 year Treatment compliance: not stated
Outcomes	Serious adverse events: Complex visual and haptic hallucinations Case 1 Methylphenidate, 1 year: visual and haptic hallucinations starting around 1 hour after drug ingestion Placebo substitution of methylphenidate: immediate cessation of hallucinations > 2 years follow‐up: no psychiatric symptoms reappeared Case 2 Methylphenidate, short period: visual and haptic hallucinations starting 2 hours after drug ingestion, continuing for almost 2 hours Discontinuation of methylphenidate: no recurrence Re‐challenge with methylphenidate: immediate recurrence of hallucinations 3‐year follow‐up: uneventful Case 3 Methylphenidate, several months: visual and haptic hallucinations Discontinuation of methylphenidate: hallucinations ceased 2‐year follow‐up: no recurrence
Notes	Funding/vested interests: the authors received a 1‐year research grant in excess of USD 10,000 from Novartis in 1997 Authors' affiliations: no other affiliations to pharmaceutical companies stated Key conclusions of the study authors: we describe 3 children with ADHD who were treated with low doses of methylphenidate and developed complex visual and haptic hallucinations Comments from the study authors: the causal role of methylphenidate in the development of hallucinations was based on their appearance after ingestion of the drug, resolving after its withdrawal, and the absence of psychiatric comorbidity that could explain such phenomena. In 1 patient, the hallucinations reappeared after an inadvertent re‐challenge. Because methylphenidate is a widely used, well‐studied, and safe pharmacologic agent, physicians who prescribe methylphenidate should be aware of even rare adverse manifestations occurring at therapeutic doses Supplemental information regarding IQ and ADHD diagnostic criteria received through personal email correspondence with the authors in October 2013 (Shalev 2013 [pers comm])