Table 3

Results of the pharmacological class identification questionnaire

Test drug	Dose (mg/70 kg)	Placebo	Opioid	Barbiturate/ Benzodiazepine	Other
		%
Hydromorphone	0	100
	0.125	100
	0.25	84	16
	0.5	63	38
	1	38	59		3
	2	38	63
	3	16	84
	4		100
Pentazocine	0	100
	4	94	6
	8	97	3
	16	59	41
	32	25	69		6
	64	31	38	19	13
Butorphanol	0	100
	0.375	78	9	13
	0.75	72	16	13
	1.5	28	38	28	6
	3.0	13	56	31
	6.0	13	41	34	13
Nalbuphine	0	88	13
	1.5	75	25
	3	50	50
	6	53	47
	12	38	38	25
	24	13	63	25
Buprenorphine	0	100
	0.055	84	3	13
	0.11	97	3
	0.22	66	34
	0.45	19	81
	0.9	9	91

Percentage of identifications of each test drug dose out of 32 responses (four responses for each of eight subjects). Identifications as phenothiazines, stimulants, phencyclidine, and hallucinogens were combined and listed as Other. Not all rows add to 100% due to rounding.