It wouldn't hurt to go a few days without it, though. As I understand it, one of the things caffeine does is release sugar from your blood - which perks you up. She described it to me as being "allergic to caffeine". I do the stupidest things and sleep for hours on end without ever feeling rested. I went out with a girl in High School who had this exact condition. If coffee makes you feel weird, it could be caused by low caffeine tolerance, stomach sensitivity or even pregnancy. It's kind of like I still get increased heart rate, etc, from drinking it, but the mental clarity that used to come from it is gone. Get a TSH [thyroid-stimulating hormone] test, and. But if I'm already concerned about something, one cup is enough to kick my butt into nervous-dude-mode. I dont understand why, several times after (a very rare) coffee or energy drink, i felt like i could hardly stand up, i was weak shaky, dizzy and tired. Good luck. You might be dehydrated. How's your weight? Drink a couple of glasses of water, maybe? Caffeine has this effect when you've had it regularly. Caffeine is precisely that type of drug: you tend to need more and more to get the same effect. Thanks everybody! I should have mentioned: I don't actually don't drink much coffee. I get absolutely no stimulating effects. I'm eager to see the answers given because I too have experienced the same thing. Hope all is well. Please try again later. If you are depressed and aren't thinking clearly (by virtue of not processing things fast enough), then perhaps speeding things up only has the effect of making it hard for you to focus. Caffeine has always made me tired rather than alert, which I've found strange. I used to get something like this if I was stressed or nervous or otherwise predisposed. I find that at least every other month I have to decrease my coffee intake because I naturally suffer from a bit of GAD. | … Recently, coffee makes me mentally confused and foggy... confused to the point that it's sometimes hard to follow conversations. I have a similar condition. My first impression is that this probably has nothing to do with coffee. Ask MetaFilter is where thousands of life's little questions are answered. (so very not a doctor) Have you been eating regularly? Recently, coffee makes me mentally confused and foggy... confused to the point that it's sometimes hard to follow conversations. i guess thats a good thing. The US Food and Drug Administration (FDA) allows 3,000 food additives to be used in our food supply. My mom tested positive for covid and she insists she’s not contagious and she won’t stay isolated. First and for most, please go to the doctor for a check-up, letting them know what happens when you drink coffee. Coffee with milk? This feature is not available right now. I had a whole array of symptoms including extreme tiredness that vanished *poof! Join 6,449 readers in helping fund MetaFilter. It doesn't seem to matter how much I drink, it doesn't make me more alert. Of course they have to do a blood test in order to tell what the count is etc. I know my reaction to caffeine varies wildly depending on what else is or isn't in my system. Plain coffee? All posts copyright their original authors.