Psychedelic Phenethylamine form the DO-x family : DOM DOC and DOB are psychoactive chemicals similar in nature to LSD but with a longer duration.
They are best known for several well-publicized, non-fatal overdoses in the late 1960s, when sold under the name STP.
STP stands for Serenity , Tranquility and Peace !
It requires only very small dosages to produce full effects like LSD.
Nowadays a Very big part of the LSD sold ( in blotter paper units) are from the DO-x family ...
You can differentiate the Psychedelic Phenethylamine form LSD by its bitter taste and its upper feeling as opposed to LSD ...

LSD is rapidly absorbed after an oral dose and initial symptoms usually appear within a few minutes; visual illusions and perceptual distortions occur within the second or third hour.
First perception of drug action occurred as late as 2-4 hours after oral doses of DOB .
A pharmacokinetic study showed that DOB (or a metabolite) began to concentrate in the brain only 3 hours after an oral dose. DOB is said to have a longer duration, 12-24 hours, than LSD, 8-12 hours.
Both of these characteristics of DOB match those of the drug ingested in Dr. Lake and associates' case --slow onset (3 hours) and a long recovery time (18-24 hours)- as well as or better than do those of LSD.