Take the following precautions:

Drink an extra four glasses (eight ounces each) of non-alcoholic liquids.
Keep your bandage on and dry for the next five hours, and do not do heavy exercising or lifting.
If the needle site starts to bleed, raise your arm straight up and press on the site until the bleeding stops.
Because you could experience dizziness or loss of strength, use caution if you plan to do anything that could put you or others at risk of harm. For any hazardous occupation or hobby, follow applicable safety recommendations regarding your return to these activities following a blood donation.
Eat healthy meals, consider adding iron-rich foods to your regular diet, or discuss taking an iron supplement with your health care provider to replace the iron lost with blood donation.
If you get a bruise Apply ice to the area intermittently for10-15 minutes during the first 24hours.After that, apply ;warm,moist heat to the site intermittently for10-15 minutes.A rainbow of ;colors;may occur for about ten (10)days
If you get dizzy or lightheaded: Stop what you are;doing,lie down, and raise your feet until the feeling passes and you feel well enough to resume activitie safely.
And remember to enjoy the feeling of knowing you have helped save lives!
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