Yes very powerful, very dangerous,very easy to o.d. on the shit.
Banned in most countries.I remember taking some (or maybe not - remember that is), and they tell me I ran around exposing meself (geezers another Jim Morrison) and running amok.
Nimbies (nembutol),reds (seconal),and tooies(tuinol) were very popular.And i must admit i did have fun on them.You become very disinhibited and will do almost anything.And the high is like having lots alcohol - that very merry feeling - without their side effects.