I occasionally inject i.v. drugs (from sterile ampules from a trusted hospital source.) Though I use a sterile syringe/needle each time and swab the area first..etc., every time I shoot I get a big needle bruise at the injection site. Is there any way to prevent this/attenuate it or should I just find other ways to take my drugs?
I normally use either 30 or 31 gauge needles 8mm.
I recommend you this manual , I hope you can find some information useful for you:
http://harmreduction.org/wp-content/uploads/2011/12/getting-off-right.pdf