No. You're much better off swallowing them. If you have a serious infection, or if you think a needle or something was contaminated, go to the ER. You're more likely to make your problem worse by trying to inject ampicillin.
Don't take antibiotics just because you think you might have an infection, you have to go to a doctor, get a bacteria culture and a antibiotics regime your doctor thinks will work best.
Injecting pills is always dangerous and taking an antibiotic just once or twice and then stopping it is a great way for bacterial resistance
Its already been said.. With antibiotics u really want to have them prescribed and follow the regimen completely or the bacteria could get resistant. I think u can get MRSA this way? N can't imagine trying to bang One of those big boys haha Do Not.