After researching a bit, I've read that 'Once ingested, psilocybin is rapidly metabolized to psilocin, which then acts as a partial agonist at the 5-HT2A and 5-HT1A serotonin receptors in the brain'. Does this mean it would cause a negative effect if you wanted to take mandy, so soon after? The only experience I have to account for isn't really a strong case - dropped one night at bestival, then the day after had some shrooms and they did a good enough job (granted it was only 2g of libs) and then dropped some more mandy at night as well, but the mdma effects were non-existant, which i guess i can only blame on dropping the night before?
Also is there a cross-tolerance with mdma & 2cb at all?