Stimulant-caused insomnia versus untreated ADHD keeping you awake: how can you actually tell which one it is?

The practical way to tell these apart usually comes down to timing and pattern rather than how the sleeplessness feels in the moment. Stimulant-caused insomnia tends to track fairly closely with how long the medication is actually active in your system, trouble falling asleep specifically on days you took a later dose, or specifically during the hours your particular formulation is still working. Sleep difficulty from untreated ADHD itself tends to look different, often described as an inability to quiet racing thoughts or wind the brain down regardless of when the last dose was taken, and it can show up even on days off medication entirely. If the change is persistent, distressing, or affecting daily functioning, contact your provider through the FasTreat portal rather than changing medication on your own. Related reading: https://www.fastreat.com/en/blogs/adhd-sleep-problems-insomnia-relief-tips References: https://www.caddra.ca/canadian-adhd-practice-guidelines/