Why not create a painless hypodermic needle? The needle will have a jagged outer surface, much like the outer surface of the proboscis of the mosquito. The jagged surface will allow only a small amount of the surface to contact the nerves in the skin, creating a minimum amount of discomfort. Once the jagged sheath of the needle penetrates the skin, a smooth tube will move through the sheath, delivering drugs or taking blood.

I heard that it is possible to create a drug addiction vaccine to help users kick the habit. The vaccine will be a combination of cocaine like chemical and an inactive cold virus. It will bind to the cocaine in the bloodstream and prevent it from reaching the brain.