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Bloodwork and Fatigue/Weakness

Posts: 1,804 Member
edited December 2024 in Health and Weight Loss
Howdy, Pals!!
How is Everyone?
I want to first assert that I searched the discussions about this before posting my own questions.

This morning I had some blood drawn to assess my hormone levels. I was in a fasted state. I drank about 64 ounces prior to the tests (and sipped on more water during and immediately afterwards).
I felt really drained, weak in the legs (and just my muscles overall). I experienced prominent lightheadedness and dizzy spells. These symptoms lasted until the late afternoon.

My lab work required about 8 vials, but I didn't think that was enough to trigger symptoms like this - especially for several hours after the procedure. I should also mention that I tend to get very anxious and nervous (even days) prior to bloodwork, so I reckon the psychological stress could exacerbate those symptoms.

I guess I am trying to ask if you all have had or have heard of similar experiences. Is this typical of getting blood drawn -- and not donating blood in larger amounts?
How has bloodwork affected you all-- as in energy levels, appetite, etcetera -- and for how long?

Thank you.

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Replies

  • Posts: 195 Member
    When did you eat after having your blood test?
  • Posts: 849 Member
    So if you were having blood tests done that required you to fast prior. In general that means nothing to eat or drink 10 to 12 hours before the blood is drawn.

    The only time, I then drink additional water prior to the test, is a minimum amount to take medication. And yes, I admit often at the lab where I go, I end up drinking another 12 oz or so. So I can do the pee in a cup. As they seem to these days always want to run a few tests on the urine.

    So did you eat directly after having your blood drawn? And I honestly cannot remember the last time that it took 8 vials. To me alot is when it is 4. I think 5 is the top number I remember ever having drawn.

    I have been tired a few times after tha 4 range. But normally make sure to eat something within an hour after being done. A few times a bit lightheaded but does not last long. And all this with being a diabetic as well.

    I do think self induced anxiety and stress over labwork is a realthing and could cause some of the issues you mention. I have a friend that has big issues around this. And I often drive her, because she has down the about passing out in parking lot afterwards. And the big issue is she gets so anxious beforehand.
  • Posts: 1,804 Member
    edited January 2020
    When did you eat after having your blood test?

    Firstly, thank you so much for reading and responding.

    I had my blood drawn around ten o'clock in the morning, then fixed my (very large) meal around two-thirty (2:30). I sat down to eat around three o'clock 3:00.

    I usually schedule my eating windows like this. I don't eat until the afternoon.
  • Posts: 698 Member
    Eight vials is a lot, especially fasted. I have to get a fairly comprehensive physical exam biennially for work, which includes four vials for bloodwork. This past August I got really lightheaded and my vision got just a bit hazy around the edges. I'm thinking if they took more I may have fainted. I wasn't dehydrated either (I'm good about that); however, I hadn't eaten since probably 6pm the evening before so was >14 hours fasted. I felt better after I ate and back to normal within a few hours. The nurses have mentioned to me that for this particular exam some people will leave after bloodwork to go eat and then come back to finish the rest of the physical.

    Did you mention your dizziness to the nurse/phlebotomist? They usually have orange juice or something on hand for exactly this reason.
  • Posts: 195 Member
    I agree with the poster above. Its good that you drank water before your test, that meant you had nice plump veins. I do know you can drink too much water, how much is too much, I dont remember. Oh, and anxiety can embrace all kinds of not so pleasant "top drawer " feelings. I suffer from anxiety and certainly from time to time have felt the way you do. But, once I get home and surrounded by my fur babies and I have eaten...things really start to feel so much better
  • Posts: 11,285 Member
    I get blood drawn frequently.

    Over how many hours did you drink the 64 oz of water? Did they tell you to drink that amount?

    I eat immediately after the blood draw. I had 17 vials taken twice (to get on kidney transplant list.) Note: the vials look like they contain more blood in them than they do!!!) And you have quarts!!

    Take a snack - at least - next time!!
  • Posts: 28,055 Member
    mytyglotz wrote: »

    Firstly, thank you so much for reading and responding.

    I had my blood drawn around ten o'clock in the morning, then fixed my (very large) meal around two-thirty (2:30). I sat down to eat around three o'clock 3:00.

    I usually schedule my eating windows like this. I don't eat until the afternoon.

    I'm with the VA and my hospital gives us a voucher for free food from the cafeteria so we can get something to eat immediately after the blood draw.

    I understand that eating in the afternoon is your preference, but your might want to reconsider this for days you get blood drawn.
  • Posts: 975 Member
    Vaso vagal response is common with blood draws and makes you feel crappy for awhile afterwards
  • Posts: 15,532 Member
    Most of those vials are 3-5 mL. Assuming the top number for all, that would be about 40mL total. Just over a shot glass worth. Your body holds over a gallon of blood.
  • Posts: 6,252 Member
    What is your height/weight and body mass?

    Physiologically? Probably not. 8 vials ~ 68 mL.

    Psychologically? I watched a perfectly healthy woman go from a typical conversation to circling the drain and clinging to life in less than two minutes because my partner looked similar to a man who had abused her as a child.

    There may be something you aren't aware of that's causing a degree of unrealistic fear regarding bloodwork.

    I'm a regular donor and drink a V8 or something similar after donations/draws and this helps.
  • Posts: 3,771 Member
    Besides the issue of not eating, you probably drank too much water. You dilute the electrolytes in your blood too much. Hyponatremia can kill you, so be careful with drinking a lot.
  • Posts: 1,804 Member
    edited January 2020
    kshama2001 wrote: »

    Since all the posters but one said you should eat or drink after having blood drawn but you don't mention this in your response, I'm checking in to make sure that recommendation sank in.

    Hello, again!!
    This is my check-in to your check-in: (:

    I am sorry I did not respond sooner - I hope my delay did not cause any concern.
    I also apologize for not conveying that, yes, I was receptive to that recommendation. I didn't mean to overlook it in my response. All of your advice, especially about re-fueling sooner after bloodwork, is very reasonable.
    I did mention continuing to drink water after the bloodwork - but I did not actually eat until a few hours later (partially due to being out of the house still, and also due to my usual routine. I feel eating in the afternoon, then ending my feeding window a few hours prior to bedtime is much easier on my digestive system. I also don't like to eat "on the road" or away from home, because I enjoy my meal and digest it much better when I am able to relax - which I can best achieve at Home. I realize that that makes it kind of hard to adjust to changes in my routine, and that I seem very inflexible. That's something I am working on - but I honestly like the idea of eating at Home, with family, and in refuge from the stress of the day.)

    Thank you for caring to reach out and make sure I understand that sufficient nutrition is crucial to recovery.
    It really means a lot more than words can express that there is a whole community of practical strangers who sincerely care about each other and do what they can to help them figure things out.
    **Edit to also add that I am feeling much better - one day after the bloodwork, in case anyone was wondering. But that shouldn't come to much a surpirse - sleep, hydration, food, and getting back to my regular routine was sufficient to getting out of that little funk!!
    ...and I only have a little yellow speck as a bruise. It's kind of cute. I could draw two little dots and a "u" to make a smiley face.
    But I won't, because that would be a bit weird.**
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