# Failed at giving blood.... **URL:** \ **Category:** Factual Questions\ **Created:** [November 18, 2010, 4:09am UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067 "2010-11-18T04:09:15Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![jennoclem](https://avatars.discourse-cdn.com/v4/letter/j/b9e5f3/32.png) [@jennoclem](https://boards.straightdope.com/u/jennoclem)\ **Post date:** [November 18, 2010, 4:09am UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/1 "2010-11-18T04:09:15Z")
I would like to know why I was not able to fill even a pint of blood when I tried to donate. I was very cold, would that matter? ---
**Author:** ![Rigamarole](https://avatars.discourse-cdn.com/v4/letter/r/77aa72/32.png) [@Rigamarole](https://boards.straightdope.com/u/Rigamarole)\ **Post date:** [November 18, 2010, 4:17am UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/2 "2010-11-18T04:17:23Z")
Are you a zombie, or a robot? ---
**Author:** ![BorgHunter](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@BorgHunter](https://boards.straightdope.com/u/BorgHunter)\ **Post date:** [November 18, 2010, 4:21am UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/3 "2010-11-18T04:21:32Z")
> [@Rigamarole](#): > > Are you a zombie, or a robot? Why not both? You got something against zombots? ---
**Author:** ![GilaB](https://avatars.discourse-cdn.com/v4/letter/g/8e7dd6/32.png) [@GilaB](https://boards.straightdope.com/u/GilaB)\ **Post date:** [November 18, 2010, 4:23am UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/4 "2010-11-18T04:23:15Z")
I find that if I don’t really, really hydrate myself before going, I have a lot of trouble filling the bag. I have low blood pressure and tend not to drink that much on a normal day. ---
**Author:** ![Rigamarole](https://avatars.discourse-cdn.com/v4/letter/r/77aa72/32.png) [@Rigamarole](https://boards.straightdope.com/u/Rigamarole)\ **Post date:** [November 18, 2010, 4:25am UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/5 "2010-11-18T04:25:49Z")
> [@BorgHunter](#): > > Why not both? You got something against zombots? Not at all. In fact, some of my closest friends are zombots. ---
**Author:** ![kenobi\_65](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kenobi_65/32/13178_2.png) [@kenobi\_65](https://boards.straightdope.com/u/kenobi_65)\ **Post date:** [November 18, 2010, 4:38am UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/6 "2010-11-18T04:38:18Z")
> [@GilaB](#): > > I find that if I don’t really, really hydrate myself before going, I have a lot of trouble filling the bag. I have low blood pressure and tend not to drink that much on a normal day. Makes sense – I know that it’s recommended that you make certain to drink lots of water on the day you go to donate. ---
**Author:** ![Paul\_in\_Qatar](https://avatars.discourse-cdn.com/v4/letter/p/ccd318/32.png) [@Paul\_in\_Qatar](https://boards.straightdope.com/u/Paul_in_Qatar)\ **Post date:** [November 18, 2010, 6:23am UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/7 "2010-11-18T06:23:45Z")
Most likely you went a little bit into shock. That reduced your blood flow. ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [November 18, 2010, 7:23am UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/8 "2010-11-18T07:23:50Z")
My father was never able to give a pint of blood despite repeated attempts. That is he wouldn’t fill a bag in a certain amount of time and the Red Cross had a time limit on how long they wanted you to try. He was told some people just have difficulty. I don’t know if that’s true. I don’t know if the reason they don’t want you to try is you’re tying up one table too long. ---
**Author:** ![phaemon](https://avatars.discourse-cdn.com/v4/letter/p/977dab/32.png) [@phaemon](https://boards.straightdope.com/u/phaemon)\ **Post date:** [November 18, 2010, 3:32pm UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/9 "2010-11-18T15:32:52Z")
> [@jennoclem](#): > > I would like to know why I was not able to fill even a pint of blood when I tried to donate. I was very cold, would that matter? It’s worse than that, you’re dead **jen**. ---
**Author:** ![Philster](https://avatars.discourse-cdn.com/v4/letter/p/13edae/32.png) [@Philster](https://boards.straightdope.com/u/Philster)\ **Post date:** [November 18, 2010, 3:38pm UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/10 "2010-11-18T15:38:15Z")
It’s worse than that. You’re dead, **jennoclem**. Even zombies appreciate proper grammar. ---
**Author:** ![Scubaqueen](https://avatars.discourse-cdn.com/v4/letter/s/c0e974/32.png) [@Scubaqueen](https://boards.straightdope.com/u/Scubaqueen)\ **Post date:** [November 18, 2010, 3:43pm UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/11 "2010-11-18T15:43:22Z")
experienced donor here. with my b negative blood (second rarest) they’re forever calling me to donate. i think i’m to four gallons or something now. drinking water does keep your veins from shrinking, which is generally the main culprit behind people not being able to donate. the large bore needle has to go in just right, or it ends up against the vein wall. that can be a real owie \*and \*trash your attempt to donate if your veins have condensed. as mentioned if you want to donate that day, you will have to drink far more water than you’re apparently accustomed to - beginning pretty much the day before. low blood pressure can also hinder donations as well as a bad stick. the pre-screen will determine if your BP is good enough, so no worries there. good luck next time. ---
**Author:** ![Postariti](https://avatars.discourse-cdn.com/v4/letter/p/b4bc9f/32.png) [@Postariti](https://boards.straightdope.com/u/Postariti)\ **Post date:** [November 18, 2010, 5:08pm UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/12 "2010-11-18T17:08:08Z")
I have difficulty even giving a small vial of blood for a blood test. My blood pressure drops, and the blood just stops flowing. I’ve been told this is a pretty common reaction. Have you ever given blood before? ---
**Author:** ![sqweels](https://avatars.discourse-cdn.com/v4/letter/s/f19dbf/32.png) [@sqweels](https://boards.straightdope.com/u/sqweels)\ **Post date:** [November 18, 2010, 5:12pm UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/13 "2010-11-18T17:12:18Z")
> [@Philster](#): > > Even zombies appreciate proper grammar. Conjugate “braaaiiinnns…”. ---
**Author:** ![pravnik](https://avatars.discourse-cdn.com/v4/letter/p/8edcca/32.png) [@pravnik](https://boards.straightdope.com/u/pravnik)\ **Post date:** [November 18, 2010, 5:54pm UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/14 "2010-11-18T17:54:44Z")
> [@GilaB](#): > > I find that if I don’t really, really hydrate myself before going, I have a lot of trouble filling the bag. Me too. If I’m a little dehydrated before a blood test the nurses have a really tough time with both finding a vein and drawing enough blood, but if I have a bottle or two of water before it’s much less of a problem. ---
**Author:** ![wheresmymind](https://avatars.discourse-cdn.com/v4/letter/w/91b2a8/32.png) [@wheresmymind](https://boards.straightdope.com/u/wheresmymind)\ **Post date:** [November 19, 2010, 12:01am UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/15 "2010-11-19T00:01:31Z")
Pshaw, whole blood’s for amateurs :-). Experienced plasma-seller here (880 ml, twice a week), confirming that hydration helps A LOT to keep your juice flowing. As Scuba mentioned starting the day before is key if you’re body’s not used to being drained. ---
**Author:** ![Digital\_is\_the\_new\_Analog](https://avatars.discourse-cdn.com/v4/letter/d/a88e4f/32.png) [@Digital\_is\_the\_new\_Analog](https://boards.straightdope.com/u/Digital_is_the_new_Analog)\ **Post date:** [November 19, 2010, 2:01am UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/16 "2010-11-19T02:01:37Z")
I get blood tests every few months. Two cycles ago, the nurse commented that I probably didn’t drink much that morning. So I asked my sister, who happens to be a certified phlebotomist. She confirmed that everyone here seems to be saying - it makes a big difference. I also have trouble after having blood drawn. It seems like a blood sugar drop. I’ve learned to take an orange juice with me, and I drink it before sitting up. (Yes, I lie down to get blood drawn…it keeps the nurse from having to catch me.) Since I started this protocol, I’ve been much better. 🙂 ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [November 19, 2010, 4:30am UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/17 "2010-11-19T04:30:06Z")
Was somebody watching you? I can’t donate when someone’s watching. ---
**Author:** ![ducati](https://avatars.discourse-cdn.com/v4/letter/d/cc9497/32.png) [@ducati](https://boards.straightdope.com/u/ducati)\ **Post date:** [November 19, 2010, 6:18pm UTC](https://boards.straightdope.com/t/failed-at-giving-blood/561067/18 "2010-11-19T18:18:55Z")
My veins collapse. Every. Single. Time. I’m a very bad stick. Blood tests, IVs - whatever - they have to stick me 2,3,4 times to get what they need. And I hate needles. Sucks to be me.