Confino‐Cohen 2005.

Methods	A patient report of pruritic maculopapular skin rash developing during methylphenidate treatment. The rash improved with antihistamines, and re‐challenge at a lower dose caused the reappearance of the rash, though less severe. Desensitisation through graded exposure of methylphenidate in incremental doses prevented further rash development
Participants	Diagnosis of ADHD: DSM‐III (subtype: not stated) Age: 8 years old IQ: normal IQ Sex: female Ethnicity: Israeli Country: Israel Comorbidity: not stated Comedication: not stated Sociodemographics: not stated
Interventions	Methylphenidate type: Ritalin Methylphenidate dosage: 10 mg Administration schedule: once daily Duration of treatment: 1 week Treatment compliance: not stated
Outcomes	Non‐serious adverse events: After a week on 10 mg Ritalin the patient developed pruritic maculopapular skin rash over the back of her hands, which spread to face, chest, abdomen, and legs within the next 2 days. Ritalin was discontinued and antihistamine treatment was initiated, and the symptoms disappeared after a week. Re‐challenge with 5 mg Ritalin was attempted. 2 days later the same itchy rash appeared on her face and chest. Ritalin was once again discontinued and the symptoms disappeared after 2 days. A desensitisation protocol was follow over 10 days with 10 mg RItalin on the 10th day. No further adverse events were noticed
Notes	Funding/vested interest: not stated Authors' affiliations: not stated Key conclusions of the study authors: allergy to methylphenidate is rare. Whenever feasible, an alternate drug should be used if a reaction to the drug occurs. When an alternative is not available or the offending drug is still the best available choice, desensitisation should be considered (for mild rather than life‐threatening conditions/reactions) Comments from the study authors: from 4 months onwards, the patient had not taken medication at weekends (1‐2 days) or holidays with no adverse reaction on readministration of the drug Supplemental information regarding IQ and diagnostic criteria received through personal email correspondence with the authors in November 2013 (Confino‐Cohen 2013 [pers comm])