I have asked this question on the Discord for a while but now I think it's time to bring it to the families. Ancient data from the Academy on effective methods of dust infusion are: 

• No data (21)
• "Ordinary" dust exposure (7)
• Traumatic dust based occurence (14)
• Natural biology (7)
• Slow infusion during duress (2)
• Just being around the Dust (1)
• Not actually initially being infused with Dust. (1)
• Other (1)

Clearly the Academy is a secretive organization lead by one plays favorites on a massive scale towards those with a dark past. This information also tells us that the best way to survive the Dust is to be caught by surprise and/or really stressed out. Unfortunately, aside from mention of breathing Dust, eating Dust and being around the Dust, there isn't enough to give us good information relating to what happens when you recieve an injection or more importantly an enema of Dust and how the effects of those are different. Can the geniuses who cow-orked on ENFER tell us more?

Most probably a dust enema will go out from your body same way it went into.