[Court]

I am not a big coffee or caffeine drinker.  I'll have a cup of coffee a few times a week or if I'm working swing shift.  About 10 minutes after I have a cup of coffee, my body instantly feels weak and my eyes start to droop.  Every time  I have any sort of caffeine this happens.  I don't know why I still drink coffee, it tastes good to me, but my body has weird affects with it.  It doesn't wake me up.  So if I can't fall asleep at night I instantly go for a cup of coffee.  

[Chanel]

Coffee relaxes me, drops my blood pressure (measured/confirmed by MD ), and can make me fall asleep within 30 mins or less after consuming it. I'd also like to understand why. This happens Even if I'm well -rested.

[Clarity]

I immediately feel increasingly tired after drinking caffiene. I recently got back from a road trip where I consumed copious amounts of coffee and Red Bull and then fell promptly asleep, which was not good for driving. I guess in some people it just has opposite effects.

[Swazzy]

I also drink coffee very rarely, mainly because I dislike the taste of all except the Mocha flavours but I do regularly take caffeine pills known as Pro Plus. My Sleep pattern is sporadic but I also function a lot better on 4-5 hours sleep than I do on 6-8 and I also have a very high metabolism. I to feel extremely sleepy within 30 mins of drinking even the exceptionally strong coffee

[Steve]

I think there may be something to how coffee reacts with ADD brain wiring. I was not diagnosed ADHD, so, dont have the hyper issue being thrown in reverse by a stimulant. I too get very drowsy while drinking coffee. Less often, I might get a short and very temporary boost, followed by the drowsiness. I have dozed off at my desk at work for a few seconds while consciously fighting to stay awake. This after drinking 2 to 4 cups of coffee each morning. The other benefits I see mentioned, that includes intestinal regularity, I have experienced as well. It also helps clear my throat in the AM from allergy generated sinus drainage. Geez, it is complex!

[SaDaF]

I have recently started having coffee as my exams are going on.. It makes me sleepy. before i used to having tea when needed,but same result.. It made me sleepy in place of waking me up..

[Mystgreen]

Oddly enough; I frequently drink multiple shots of espresso etc prior to meals to stimulate my digestion which it seems to help.  But when I drink coffee or tea in the evening or at night it also makes me drowsy and does not negatively affect my sleep.

[Ben Benson]

I found this article because I wondered why the drowsy effect of coffee was so instantaneous and like clockwork for me. It happens 10 to 20 minutes after I drink it. I even had a micro sleep just now, sitting up with my eyes open, shortly after drinking a cup. Before this, I was wide awake and full of energy. I just wanted to drink the coffee for its taste. Other hot drinks and instant coffee DO NOT do this to me, it's specifically plunger coffee or espresso. I have also had paradoxical reactions to other substances, such as a sleeping pill gave me insomnia, it was impossible to sleep for hours, and tequila acts as a stimulant but other spirits are a depressant.

[J McDonald]

I too suffer from this, I can drink 2-3 cups of coffee and fall into a deep sleep within minutes. Seems to have the opposite effect on me!

[Jenoir]

I also suffer from this problem. I've read that coffee makes you pee a lot, which makes you dehydrated, your blood thickens, causing you to feel fatigued and fall asleep. Hope this helps!

[hannah]

I drink rockstar blueberry high caffeine energy drinks and even while drinking them I fall asleep I sleep minimum 9 hours a night and usually get really tired and nap a couple hours in afternoon

[Thomas]

I had a professor that told me once that getting sleepy after drinking caffeine is a possible sign of a rare form of diabetes. (She had that form of diabetes)

[Tjspoerer]

Coffee makes me sleepy too and the days I have less I am much more alert.

[Rhea]

I don't drink coffee at all generally, but if on the rare occaison I do, I start immediately feeling drowsy and need to sleep This has always been the case with me I always thought my body/brain was wired differently

[lizz]

I can drink coffee and immediately feel sleepy.  

In fact its 12:57 a.m.
I have a flavored 16 oz cappuccino with three little shots which are supposed to each equal one shot of espresso (*each*.... and there are three in this cup)

And i am falling asleep -hence me finding this through a google search.  

-lizz-

[Nick]

I drink 1-2 mugs of coffee every morning, and I have been doing that since High School.
But I never drank it for the caffeine or for waking me up, I drank it for the sweet taste of coffee with sweetened liquid creamer. On the infrequent chance that I brew an additional pot of coffee (2 more mugs) for an afternoon drink I feel sleepy. And I only feel sleepy when in the afternoon. Even rarer is if I choose to drink coffee at night (say I'm out with friends or studying in the library or a coffee shop), it has no effect on me and it does not affect my sleep and I do not experience any caffeine crashes. I drink plenty of water throughout the day to keep hydrated and at meals, I drink one glass of fruit juice and then the rest are glasses of water. But if I miss my morning coffee I feel no symptoms of withdraw or headaches.

[Nick]

I drink 1-2 mugs of coffee every morning, and I have been doing that since High School.
But I never drank it for the caffeine or for waking me up, I drank it for the sweet taste of coffee with sweetened liquid creamer. On the infrequent chance that I brew an additional pot of coffee (2 more mugs) for an afternoon drink I feel sleepy. And I only feel sleepy when in the afternoon. Even rarer is if I choose to drink coffee at night (say I'm out with friends or studying in the library or a coffee shop), it has no effect on me and it does not affect my sleep and I do not experience any caffeine crashes. I drink plenty of water throughout the day to keep hydrated and at meals, I drink one glass of fruit juice and then the rest are glasses of water. But if I miss my morning coffee I feel no symptoms of withdraw or headaches.

[M]

ADD & ADHD
If it makes you drowsy almost immediately it is not a crash or anything similar. Those who mentioned ADD and ADHD are correct. Stimulants all effect ADD and ADHD including caffeine. Drinking something with caffeine can focus and calm those with the conditions, even aiding in sleep. University studies have shown caffeine may be a viable option in replacing heavy stimulants like Methylphenidate in children and adults with ADD and ADHD.

http://psychcentral.com/lib/caffeines-effect-on-adhd-symptoms/0003050

[Guest]

I fall sleepy immediately with coffee. I find it helps me concentrate on sleeping and eliminates my rapid random thoughts that tend to keep me awake.

[Amy]

It seems there are so many of us that have this problem that the Naked Scientist's responses seem quite naive. It just shows the complexity and variety present in the human population. I am exactly the same as Angie, I can often have a cup of coffee and be bouncing off the walls, on other occasions I literally need to nap for a couple of hours afterwards (the drowsiness sets in within around 5-10 mins of drinking the coffee). Luckily it's a Saturday today (after the drowsiness set in) so I was able to have a sleep after my coffee. I drink one cup of coffee everyday after breakfast.
A strange phenomenon, but glad to hear there are others who have this problem, and hopefully we can get to the bottom of it one day!