The NBOMe series of drugs are psychedelic derivatives of the 2c-x compounds, but much more potent. Doses active around 250ug (average doses from 500ug-1mg) and have been noted to be extremely temperamental between users and even in the same users. There have been more than a few hospitalizations and deaths from apparent use of NBOMe, typically insulfiated powder but incidents have been reported from tabs. Tread carefully if you intend to use these drugs, they are highly potent and i would certainly not use them as an LSD replacement. I have a lot of experience with them, and can say that they do have value, they are not worth the risks and side effects, short and long lasting.
They also have been known to cause psychotic breaks in typically mentally healthy people, so watch for that too. If you decide to take NBOMe start very very low and never eyeball powder, always use accurate measuring techniques. I suggest taking a 1/4 or even 1/8 of a tab to start if that is your ROA. Also, they are typically not active orally only sublingually with tabs. Be careful, dose low and don't make nbome use a weekly thing, because i assure the long lasting side effects are not worth it.
These side effects can include anxiety, depression, down regulation of 5-H2 receptors and HPPD.
short term effects can include vasoconstriction, heart issues/failure, nausea, seizures, delusional thoughts and erratic behavior. There is a lot i know i am missing but you can use Erowid.com to get a more accurate synopsis on these drugs.
Stay safe!