First off: I am still undiagnosed. I’ve followed the ADHD topic for more than a year now since I seem to match a whole lot of symptoms and behavior patterns. An official diagnosis will most probably still take another year. I live in Germany.
One thing that got me wondering was caffeine. As I’ve heard, drinking coffee will make ADHD folks not feel any more awake, maybe even a little tired.
While it doesn’t make me feel awake as well, I very vividly remember my first coffee a long time ago that caused a massive outburst of productivity when all of the time I was known for being ‘lazy’ and distracted. However the effect quickly diminished with each subsequent coffee over the next year.
Isn’t this a contradiction though? If I actually had ADHD, why did coffee have this awakening effect on me back then?
The way caffeine works is that it blocks the receptors in the brain for adenosine, which is responsible for slowing down the neurons in your brain, making you feel sleepy. It also causes the release of adrenaline, which is a stimulant and thus can help ADHD brains focus. Additionally, it makes your blood vessels (especially in your brain) constrict, which can make other stimulants take effect faster. As if that weren’t enough, it also slows dopamine reabsorption, which feels rewarding (the major contributor to caffeine addiction).
These are the upsides, but caffeine comes with serious downsides if you use it regularly (i.e. more than twice a week). In particular, it seriously inhibits your ability to get truly deep, restorative sleep, even if you only have it in the morning.
Tl;dr: It can make you feel more awake, but it can’t replenish your energy stores. It basically puts a pin below the needle of your mental fuel gauge so it can’t drop below half a tank, but doesn’t actually fill the tank.
Read more in this fantastic piece: https://science.howstuffworks.com/caffeine.htm
It’s not a universal rule at all. I know people who are very ADHD who if they drink coffee they have a panic attack. I know people who it makes tired, and I know people who it makes productive. Personally it makes me more talkative.
Basically, it’s not a criteria for diagnosis at all. Everyone’s brain chemistry is different. There might be a higher percentage of people with ADHD whom caffeine does not affect compared to the general population, but that does not at all mean that to be ADHD you have to have that same thing.