There are a few benefits.
* 2-5 seeds of Datura stramonium chewed right after taking mescaline or cacti will pretty much get rid of most of the nausea some people get from cacti or mescaline. So this is one reason people like this combination.
* Hyoscyamine (the main active in Datura stramonium seeds) potentiates the effects of nearly all psychedelics. With mescaline in particular, it adds more depth to the visual effects, and can also increase the euphoria.
* It can also greatly increase the potency of micro doses of mescaline, but doesn't do much for larger doses. This means you can take 2-5 seeds, and then a dose of mescaline that would normally be almost not enough to feel it and get very decent effects from the mescaline.
Make sure you don't take a dose large enough to cause physical symptoms such as dry mouth, dry skin, etc. You want to take a dose of the seeds that's just enough to alter the effects of the mescaline, and not enough to do anything on its own. For most people that means 2-5 seeds. Some people are a little extra sensitive and should only use 1-3 seeds.
Datura stramonium seeds in this dosage range have no mental effects at all. On their own at less than 10 seeds they might cause very slight euphoria and slight stimulation, and that's it. Some people might experience a little dry mouth or dry skin. There are no other effects at such a small dose. This dose is safe and many times below the dose needed for mental effects.
You'll be surprised at just how versatile these seeds are. They go well with a lot of things in these small doses. Many people find they do wonders for HWBR and morning glory seeds. They can also boost the visuals of LSD.
You may remember me as 69Ron. I was suspended years ago for selling bunk products under false pretenses. I try to sneak back from time to time under different names, but unfortunately, the moderators of the DMT-Nexus are infinitely smarter than I am.
If you see me at the waterpark, please say hello. I'll be the delusional 50 something in the American flag Speedo, oiling up his monster guns while responding to imaginary requests for selfies from invisible teenage girls.