I recently made a brew of 20g Acacia confusa root bark. I boiled it for about 15 hours total, doing at least 8 boils. I used it with a 5g syrian rue brew. The DMT was definitely properly activated. So I know that some amount of DMT was extracted from the root.

I froze the left over solids and I'm now rebrewing the previously used acacia root. I've done 4 one hour boils so far. Each boil has turned a deep brownish red color. This color isn't quite as intense as it was when I brewed the material last time, but the color is indicating that something is being extracted.

Have other people tried reusing DMT herbs a second time after they already successfully brewed them? Did it extract any more DMT? Or was it a waste of time?

I'll report back with the results of my experiment.

waste of time.

If remaining DMT is a concern its recommended to soak the remaining plant matter in a small amount of vinegar or some basic solution and extract from it. At this point (continuing to boil) you're breaking down the plant matter and the result wouldn't have nearly any DMT at all after such a thorough boil, and in your case probably won't be worth extracting from either, but it's a good way to reassure yourself that you're not throwing out the goods if its a concern. But it's super unlikely. People do it after boils that were much less extensive than yours.

The result of an extraction attempt wouldn't be all that satisfying either but it will put your mind at ease. Probably dark red goo that's mostly inactive.

I finally reused the Acacia confusa root bark from my previous anahuasca trip. I did 10 boils for 1hr each. I used a 3g syrian rue brew as the MAOI, 30 minutes before the Acacia.

40 minutes after drinking the Acacia, I experienced a moderate mood lift and mild stimulation. This contrasted greatly with the sedation caused by the rue and Datura (I took a small dose of Datura before the rue as an antiemetic).

So there was some effect from the Acacia, but it was very mild. It probably isn't worth it to reuse DMT herbs to make a second brew if you only have a small amount of herb. But I think that in the future I'll save up all my already brewed herbs and rebrew them once I collect a larger amount. If I had had 60g of used acacia, it might have actually had some psychedelic effects.

On a slightly unrelated note, I didn't expect the reused Acacia to be very strong. So I also combined it with a low dose of fly agaric. There seemed to be a little synergy and the effects were nice, but it was still quite mild. The calm and serene state of mind that fly agaric induces in me was compounded, but the mental effects and visuals weren't increased. To be honest, the dose of fly agaric was low enough that the visuals and mental effects would have been minimal any way.

This combination would have been a lot more interesting using higher doses.