Why do they need to inject the needle directly into the vein?

Question

The whole arm is full of veins and pumping with blood, why can’t they just inject it anywhere or move downwards, down the arm? Why do they HAVE to inject it in the beginning of the bicep/beginning of arm area?

In: 0

Answer 1

That is a common area to use because there is a pretty consistent, fairly large vein there that is close to the surface. The veins closer to the hand tend to be smaller, and it may be hard to get a big enough needle into them without going completely through the vein, missing it etc. Veins in the hand/forearm tend to “roll” around more, also making them harder to use.