It depends also on if the "needle" could be able to penetrate Supermans skin to be able to seep the kryptonite into his blood because the needle might just snap in half or something and not even go through his skin.
I put an answer out last month to "What actually Happens to Superman when he is exposed to Kryptonite?" question which may address this directly. You can check it out here to get some perspective:
What actually happens to Superman when he is exposed to kryptonite?
The simple answer?
This depends on the amount of Kryptonite in proportion to sunlight ...