When you get a shot in the arm, how can you be sure the contents are being released into a blood vessel?

Question

When you donate blood the needle goes into a large, visible vein in your arm or hand but when getting a shot the needle just goes somewhere in your arm.

In: Biology

Answer 1

Nurse here, normally when you get a shot in the arm, you don’t want the contents to be released directly into the blood vessel. Normally we inject into your arm muscle tissue and retract the plunger, looking for blood return. There shouldn’t be any blood return since muscle tissue isn’t saturated with free flowing blood. Otherwise, if you do want contents to be released into the blood stream directly then you go for the veins.