Table 2.

Binding affinities (Ki, nM) of various hallucinogenic tryptamines and ergolines mentioned in the text at selected central serotonin sites, and estimated hallucinogenic potency and duration of action (following oral administration) in man. Where possible, affinities are listed as determined by competition binding versus an agonist radioligand. Affinities for receptors in the inactive conformation (determined by saturation binding assays versus an antagonist radioligand) are generally lower (higher Ki values) for all compounds, and are indicated in the table by a superscripted asterisk. Dashes in cells denote no data on affinity at that receptor, while N.A. signifies a lack of hallucinogenic activity (but see text for more on this). Full references to the source articles, denoted by superscripted numbers, can be found in the References section.

DRUG	5-HT1A	5-HT2A	5-HT2C	Hallucinogenic potency in man	Duration of action in man
Psilocin	49.00 174	25.00 174	10.00 174	10 − 20 mg 118	3 − 6 h 118
LSD	1.10 175	3.50 175	5.50 175	60 − 200 μg 118	8 − 12 h 118
Lisuride	0.15 176	1.40 177	5.30 177	N.A.	N.A.
DMT	119.51 178	230.27 178,*	-	> 350 mg 118	≤ 1 h 118
5-MeO-DIPT	35.00 29,*	5,620 29,*	1,700 29,*	6 − 12 mg 118	4 − 8 h 118