How long must I wait before having CO2 after filler on acne scars? (Photo)

There is some theoretical concerns that the treatment of the skin with a laser might make the filler go away more quickly. I usually wait six weeks after the filler before proceeding with laser treatment.

Hello kevTHo, 
Good question.
Depends upon the filler and work performed. If a filler procedure was performed for something like wrinkles, which is and can be a very shallow application of fillers you would likely benefit from waiting until most of the filler effect went away. 
In other words, fillers placed shallow are more likely to be adversely impacted or be noticeable in newly tightened skin. Fillers placed deeper are less likely to be directly impacted. 
However, though a deep filler is unlikely to be impacted after a couple weeks of placement, remember that your skin will tighten. Therefore, its important to assess where it may end up as the skin moves and how it may look. Will you have a bump or ridge where not intended? 
Most of the time it will be OK, but I have seen some end results not be as desired. There are too many factors to list. A good practitioner should be able to help make that judgement call. 
In the ideal world, I prefer to tighten skin first, then ad the accents. This is not a requisite, only a preference.
I hope the above helps. I hope and wish you achieve everything you hoped for.
Warmly,
Arbella Sarkis, MD