Table 2.

Percent of Fentanyl Remaining in TDS After Skin Permeation Experiments and Percent Recovery in the Experiments.

	Percent Remaining in TDS After Each Protocola								Percent Recoveryb
	1	2	3	4	5	6	7	8	Average, All Protocols
	no Heat	11–12 h	18–19 h	6–72 h	24–72 h	48–72 h	multiple Heat	0–72 h
TDS-Z	66 ± 10	98 ± 5	94 ± 3	48 ± 7	60 ± 4	61 ± 8	58 ± 4	58 ± 10	110 ± 2
TDS-V	52 ± 5	76 ± 3	74 ± 3	35 ± 5	35 ± 8	37 ± 7	35 ± 6	32 ± 7	95 ± 1
TDS-M	46 ± 9	87 ± 6	91 ± 2	22 ± 6	16 ± 10	26 ± 14	27 ± 10	26 ± 8	105 ± 2

^aMean ± SEM, n = 4 skin donors (3–4 skin replicates for each skin donor).

^bMean ± SEM, n = 8 protocols. Percent recovery was based on total drug content in the TDS according to the drug product labels. Percent recovery does not include fentanyl in skin; the amounts of fentanyl remaining in the skin were assumed to be small at the end of the experiments and were not determined during the extraction analysis.