After a second unsuccessful attempt to have a nice tripping day with two of my San Pedros. I would like to ask anyone who might know, how 2 X 40cm X 12cm thick cacti had absolutely no effect on me? I'm sure about my cacti strain cause of their blueish colour when young and the black hair on the flowers when they form and of course shape, spines and general appearance. The plants are at least 10 yo and seem perfectly healthy. My first attempt was drinking the cacti juice after proper preparation and the second attempt was through alcohol extract. In both cases, I didn't even feel nausea. What might be wrong?

It could be that you have a very weak or even inactive Pachanoi. Post a photo if you can. How did you prepare the "juice"?

I froze the cacti, pealed the thin layer of skin, cut the outer skin (about 1cm thick), passed it through the blender, froze it again, strained it, and drunk it. That was my first attempt a few months ago. I did quite well with the alcohol extraction which was easy to do. After 4 pulls I had high expectations and now I'm so frustrated I want to chop them all off (30 cacti) and try again with bridgesii or peyote.

Why not try to make a proper tea? Use the whole cactus, not just the dark green flesh. You dont even need to peel the skin or freeze the cutting. Just slice the cactus into thin pieces or blend it up. Boil the tea for a long time. Use a larger amount of cactus compared to last time and see how it goes. If its real Pachanoi then you should feel something. Even if you find out that it is weak and you need to use a large amount, that is still easier to do than completely starting over.

I did use the whole cactus beside the core in the alcohol extraction method. The taste was more bitter than I could ever imagine.

If its real Pachanoi then you should feel some effect, even if its not strongly psychedelic. You should still feel stoned or somehow different if you took a decent amount. But without a photo its hard to know whats really going on here.

Weak Pach is the most likely problem. Bridgesii won't let you down. 400 grams or so fresh Bridgesii is a good starting point.

I used 95% alcohol (5% distilled water)

I'm looking all day for bridgesii cacti/seeds and was looking to add some spore prints too but seems that paypal doesn't support smart shops anymore and through bank wire is not an option for me. It's getting harder and harder for the psychonauts these days. I'll find the way to it.

The OP reports eating the bitter outer tissue of over 2 feet of cacti nearly 5 inches thick!

PC is known to be extremely bitter, has a glaucous blue coating on the young stems and the hairs can indeed grow blackish brown as I have repeatedly observed in numerous flowering specimens first hand.

I suspect that the issue here is that the 10 year old plant is a PC clone and I question the identity of it as a properly identified pachanoi. The OP may also be on an antidepressant or medication which prevents the effects of mescaline, but the indication is that the material does not contain a significant amount of mescaline.

If there is a medical issue then replacing the material with T bridgesii will also result in no effects, however if T bridgesii (Echinopsis langeniformis) is effective then the initial material can be considered to be of low entheogenic value.

Or so I suspect.