Yes, ADHD (Attention Deficit Hyperactivity Disorder) can cause insomnia or difficulty falling and staying asleep. People with ADHD may experience racing thoughts, impulsivity, and hyperactivity, which can make it hard to calm down and relax before bed. Additionally, some medications used to treat ADHD, such as stimulants, can cause insomnia as a side effect. It's important to talk to a healthcare professional if you are experiencing insomnia or other sleep-related issues as a result of ADHD or medication. They may be able to provide recommendations or adjustments to your treatment plan to help improve your sleep.