Why can’t I drink caffeine before donating blood?

Why can’t I drink caffeine before donating blood?

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0 thoughts on “Why can’t I drink caffeine before donating blood?”

  1. If by ‘giving blood’, you are talking about blood donation for transfusions, then yes.
    If you mean drinking coffee prior to venipuncture for a medical blood test, the answer is also typically yes, particularly if the coffee is consumed black. Coffee is a water equivalent beverage in this context. There are certain blood tests, however, where the doc wants you no be truly fasting for a specific reason. In such cases , no sugar or cream should be added…including non dairy whiteners and sugar substitutes.

  2. I’ve never heard that. I give blood regularly. The main thing is that you are supposed to be well-hydrated and drink lots of extra water the 24 hours before you give blood. It really does help your veins plump up, make them easier to find and make the whole experience easier.
    Starting 24 hours before I plan to donate I really do tank up on water. But I drink my normal coffee in the morning and tea in the afternoon. But I don’t drink a caffeinated beverage in the afternoon (I donate in the evening).
    That advice (?) might be peculiar to the place where you are giving blood.

  3. OP: Why can’t I drink caffeine before donating blood?
    You need to be sure you are sufficiently hydrated when you donate blood. It’s recommended that you drink extra fluids (water and juices) for a couple of days prior. You want your veins to be easily seen and accessed. Being hydrated helps with that.
    Caffeine is a diuretic. That means that all the extra water you are trying to use to stay hydrated can be removed from your system when you drink caffeine.
    Caffeine affects everyone differently. If this is the first time you are donating, refrain from the caffeinated drinks until you see how your body reacts to having a pint of blood removed from it.
    Blood Donation Tips | Before, During & After | American Red Cross
    Giving Blood For The First Time? 5 Things You Should Do Before Donating Blood | The Health Guide
    Although caffeine is a stimulant and can temporarily raise blood pressure, I could find nothing that stated that was a reason not to drink it before donation.
    Caffeine can cause a short, but dramatic increase in your blood pressure, even if you don’t have high blood pressure. It’s unclear what causes this spike in blood pressure. Some researchers believe that caffeine could block a hormone that helps keep your arteries widened.
    Caffeine: How does it affect blood pressure? – Mayo Clinic

  4. It acts as a mild diuretic, hence, it could cause mild dehydration before you even start the donation process. Blood donation can deplete the volume of you blood by up to 10 % . You know how sometimes people feel light-headed and might even faint after donating? Their blood pressure drops when standing up, due to lower volume circulating. This is part of the reason for resting, and the glass of orange juice after a blood donation.

  5. Caffeine is a diuretic which will make you lose fluids by urinating. After every blood donation it is imperative for the donor to hydrate as much as possible to help replenish the blood supply that was just lost. Aside from getting dehydrated, caffeine can also increase the chance of a donor potentially feeling nauseous. If you find it really difficult abstaining from caffeinated products it would probably be good for your own health to refrain from donating blood.

  6. Yes though the caffeine may raise your blood pressure/pulse a bit, leading to you being turned away. If neither metric runs high for you a little coffee is unlikely to cause an issue.

  7. I had my two cups of coffee and donated … they would prefer you not drink coffee because it is a stimulant and may alter anesthesia and other drugs slightly?? It also can dehydrate you slightly (makes you pee more) .. big deal?
    If you have small veins and low blood pressure I could see not drinking coffee before donating as your blood will be coming out slower anyway … thicker blood from dehydration might make it slower yet.
    As far as I know, they want you to eat a normal (for you) breakfast before donating and for me, that includes coffee.

    Victor Allen’s

  8. Yes! If it’s part of your morning routine, don’t skip it and court a withdrawal headache.
    Also — eat breakfast, and lunch too if you can.

  9. I’ve done early morning donations before (around 7 am), after having eaten a normal breakfast which for me includes a cup of joe. It’s never been a problem, and it’s never raised my blood pressure or pulse to the point that I get deferred.
    You might not want to drink it right before your donation, though. If your blood bank does a routine vital sign check before your donation, it can make your oral temperature higher or lower than their standard, and you may have to wait a certain amount of time for your mouth to cool down or warm up before they take your temperature again.

    Eight O’Clock

  10. Yes you can drink coffee before donating blood.
    One thing to consider is it may raise your blood pressure a few points. If your BP is marginal you should avoid coffee for a few hours before donating.
    Original question: Can we drink coffee before donating blood?


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