What if you miss the vein injecting heroin and get infection?
If a serious bacteria was on the needle or in the drug you could get gangrene. The worse scenario would be if you didn’t miss and the bacteria went up your vein and latched on to your heart valve and got bacterial endocarditis. A bacteria that grows on your valve and eventually breaks off in pieces spreading throughout your body obstructing blood flow to your brain and limbs which could lead to a stroke.