I fee this way too. If I need to get something done anyway, I usually buy a bag of baby carrots and drink water with the carrots while I work through it. I also have some black coffee at the start.
For time frames longer than a day, for people like us, there is no substitute for going to bed earlier.
Here are my suggestions: 1. Accept that you will probably be less productive as you expect. Being angry that you're not fully productive will make you even less productive. Make your goal to be 'as productive as I can realistically be under my current circumstances'. 2. Aggressively pre-empt distractions if possible. Get rid of anything you might want to read or watch from your work environment. If you can do your wo…
Those are excellent tips for ADHD. No matter how hard you push, after attention depletes it's an uphill battle to stay productive. I just chill now and recharge, no more burning out! Better results as well, more things to show for my time in the mid term.