Why does beer give me such a headache, before I went to bed, after I drank like 20 beers ( don't get excited)

still not enough water...you were dehydrated

I don't really know. I get a migraine usually the day of or the last day of my cycle. I was wondering the same. It can be really bad sometimes. My doctor told me low iron. So I try to eat hot cereal on those days (iron fortified) but I have not been able to get rid of them completely. It's obviously something hormonal and the cause may be different with each woman. The iron for me is helping, but not solving. I also use Excedrin Migraine, as that's the only meds that work for the headache, I use the Ibuprofen just for cramps. I don't go into my GYN until April. I planned on asking then. If I ever remember I'll try to post what they said, but you know how that goes. March is a long way away!

You still didnt drink enough water and therefore you have a headache because you are dehydrated! Even though you drank water the night before you have to keep drinking it through the day to help with the dehydration.

There are some beers that I can drink and no matter how many I drink I get a headache...cheap beer usually does that to me.

Regular beer is 4%. So you drank the equivalent of about 14 beers. And alcohol is poisonous you may recall. Plus who knows what drinking more than 3 gallons of fluid in what I assume was a relatively short time did to ya.At least you didn't puke up the aspirin

Dehydration...beer dehydrates you ...therefore the headaches prevented could be done by drinking water in between...and/or...try drinking water before going to bed along with a couple aspirin...i heard that sometimes works...i personally never tried it though... I have however drank a glass of water with every beer and VOILA!...no headache...no hangover... dehydration is most likely the cause of your headaches...

GOOD LUCK 2 YA!

It's a hangover. It's no wonder, at even 3 percent, 20 beers is a lot. It's no wonder you are hungover!

It might be something about drinking 20 beers that gave you a headache fool!

it all depends on what kind of beer it is. My friends and I all used to dink miller light and over half of us always get a headache. I don't know if they put something different in it. now i drink coolers light and i am fine. you also can't mix and match.

BC ALCOHOL does that.... Have you tried that day after **** that your supposed to take the night you drink? Alcohol does that though ,it means you drank more then your body wanted or needed. Even if it was only 3 % . Drinking isn't supposed to be about quantity, its quality

honestly if you drank 20 beers in one night(unless they were 1oz beers) along with that much water you would have busted a gut and not had time to drink between trips to the pisser....

In reality you have to drink 2x as much water as you do alcohol to keep from having a hangover.

Dehydration.