Is it bad as far as sterilization to shoot half the contents on day and save half in the needle and shoot the other half the next day. 50mg ED seems to recomended over shooting 100mg EOD.
I have done it without problems, but I wouldnt recommend it unless you were in a pinch. I found myself traveling across country in a uhaul with only 3 syringes (100s of needles) and 6 days still on the road. I was taking 100mg prop and 75mg tren everyday. So I used a syringe, swapped needles - preloaded the used syringe and tossed the needle. The next day I used a fresh needle. Did that a couple times.