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?