Roughly 1 in 20 adults globally has been diagnosed with ADHD, and prevalence in younger demographics is higher still[1]. That means in a typical SaaS dashboard or e-commerce flow, around 5–10% of your active users have meaningfully different attentional capacity than the median user your interface was likely tested against.
ADHD is not a single thing. The diagnostic clusters most relevant to interface design are inattention (difficulty sustaining focus and filtering distractors), working-memory deficits (a smaller mental scratchpad)[2], response inhibition deficits (harder to resist impulses), and time-perception differences (poor estimation of elapsed and remaining time)[3]. Every one of these has a UI counterpart that, when ignored, makes ordinary interfaces actively hostile.
The good news: ADHD-inclusive design overlaps almost entirely with what we already know is good design. Lower cognitive load, clearer affordances, less motion noise, more predictability. The patterns below are not specialised accommodations; they are universal upgrades that happen to be life-changing for one in twenty of your users[4].
Each section names the pattern, explains the mechanism through which it excludes ADHD users, cites the relevant research, and ends with a concrete alternative.