Adults with attention-deficit/hyperactivity disorder (ADHD) often face delays in diagnosis and remain untreated, despite significant negative impacts. To evaluate the safety and efficacy of transdermal treatment options in children, adolescents, and adults, a systematic literature review was conducted, with a focus on the implications of transdermal therapies for ADHD in adults.

A MEDLINE/Embase/BIOSIS/SCOPUS database search was conducted December 4, 2019, for English-language articles of interventional clinical trials using transdermal formulations for the treatment of ADHD without publication date limit. Assessed outcomes included efficacy, safety, adherence, abuse potential, cost efficacy, and health-related quality of life.

Of 23 eligible publications, 18 were in children or adolescents (n = 1699; range 23-305), and 5 in adults (n = 274; range 14-90); all included methylphenidate transdermal system (MTS). All seven pediatric publications reporting change in ADHD symptomology from baseline reported a significant improvement with MTS treatment. Similarly, in three adult publications, ADHD symptoms improved significantly with MTS treatment. Safety findings in pediatric and adult studies were comparable; the most frequently reported treatment-emergent adverse events (TEAEs), namely, headache, decreased appetite, and insomnia, were reported in 13/16 (81%) of publications reporting specific TEAEs. MTS-related dermal reactions were mostly mild and transient. Discontinuation due to dermal reactions was reported in 10 studies (range 0%-7.1% [1 of 14 patients]). MTS compliance was high when assessed (97%-99%).

Transdermal therapies provide a useful treatment formulation for ADHD. Studies of MTS and other transdermal formulations, such as amphetamine, in adult patients are needed in this underserved population.

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