I'm not sure if you can. I think if you've had trouble in the past with just giving samples it might be tough. All you can do is go in and get evaluated and that doesn't take long..
They have to make sure ur veins.are big.enough bc its a good size needle theyll be putting.in.ur.vein and.i believer yu have to have a vein on each arm.
They use a 14 gauge needle for plasma donations, so the vein needs to be pretty good size. But like Brady said, you can go in and have them check your vein. It only takes a few mins.
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