Abstract
Camphor, menthol, and methyl salicylate occur in numerous over-the-counter products. Although extensively used, there have been no estimates of human exposure following administration via dermal application. Furthermore, there is little information about the pharmacokinetics of those compounds. The authors report the plasma concentrations of the intact compounds as a function of dose following dermal patch application. Three groups of 8 subjects (4 male, 4 female) applied a different number of commercial patches (2, 4, or 8) to the skin for 8 hours. Plasma samples were assayed using sensitive and selective gas-chromatographic methods. For the 8-patch group, the average maximum plasma concentrations (Cmax ± SD) were 41.0 ±5.8 ng/mL, 31.9 ± 8.8 ng/mL, and 29.5 ± 10.5 ng/mL for camphor, menthol, and methyl salicylate, respectively. The corresponding values for the 4-patch group were 26.8 ± 7.2 ng/mL, 19.0 ±5.4 ng/mL, and 16.8 ± 6.8 ng/mL. The harmonic mean terminal half-lives were 5.6 ± 1.3 hours, 4.7 ± 1.6 hours, and 3.0 ± 1.2 hours for camphor, menthol, and methyl salicylate, respectively. The 2-patch group had measurable but low plasma concentrations of each compound. Low-dose dermal application for an extended time results in low plasma concentrations of all 3 compounds. Four and 8 patches, when applied for 8 hours, gave measurable and nearly proportional plasma concentrations. Although unable to determine the absolute dermal bioavailability of these compounds, there appears to be relatively low systemic exposure to these potentially toxic compounds, even when an unrealistically large number of patches are applied for an unusually long time.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1151-1157 |
| Number of pages | 7 |
| Journal | Journal of Clinical Pharmacology |
| Volume | 44 |
| Issue number | 10 |
| DOIs | |
| State | Published - Oct 2004 |
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Keywords
- Absorption
- Camphor
- Dermal patches
- Menthol
- Methyl salicylate
- Toxicity
ASJC Scopus subject areas
- Pharmacology (medical)
- Pharmacology, Toxicology and Pharmaceutics(all)
Cite this
Dermal absorption of camphor, menthol, and methyl salicylate in humans. / Martin, Debra; Valdez, Jennifer; Boren, James; Mayersohn, Michael.
In: Journal of Clinical Pharmacology, Vol. 44, No. 10, 10.2004, p. 1151-1157.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Dermal absorption of camphor, menthol, and methyl salicylate in humans
AU - Martin, Debra
AU - Valdez, Jennifer
AU - Boren, James
AU - Mayersohn, Michael
PY - 2004/10
Y1 - 2004/10
N2 - Camphor, menthol, and methyl salicylate occur in numerous over-the-counter products. Although extensively used, there have been no estimates of human exposure following administration via dermal application. Furthermore, there is little information about the pharmacokinetics of those compounds. The authors report the plasma concentrations of the intact compounds as a function of dose following dermal patch application. Three groups of 8 subjects (4 male, 4 female) applied a different number of commercial patches (2, 4, or 8) to the skin for 8 hours. Plasma samples were assayed using sensitive and selective gas-chromatographic methods. For the 8-patch group, the average maximum plasma concentrations (Cmax ± SD) were 41.0 ±5.8 ng/mL, 31.9 ± 8.8 ng/mL, and 29.5 ± 10.5 ng/mL for camphor, menthol, and methyl salicylate, respectively. The corresponding values for the 4-patch group were 26.8 ± 7.2 ng/mL, 19.0 ±5.4 ng/mL, and 16.8 ± 6.8 ng/mL. The harmonic mean terminal half-lives were 5.6 ± 1.3 hours, 4.7 ± 1.6 hours, and 3.0 ± 1.2 hours for camphor, menthol, and methyl salicylate, respectively. The 2-patch group had measurable but low plasma concentrations of each compound. Low-dose dermal application for an extended time results in low plasma concentrations of all 3 compounds. Four and 8 patches, when applied for 8 hours, gave measurable and nearly proportional plasma concentrations. Although unable to determine the absolute dermal bioavailability of these compounds, there appears to be relatively low systemic exposure to these potentially toxic compounds, even when an unrealistically large number of patches are applied for an unusually long time.
AB - Camphor, menthol, and methyl salicylate occur in numerous over-the-counter products. Although extensively used, there have been no estimates of human exposure following administration via dermal application. Furthermore, there is little information about the pharmacokinetics of those compounds. The authors report the plasma concentrations of the intact compounds as a function of dose following dermal patch application. Three groups of 8 subjects (4 male, 4 female) applied a different number of commercial patches (2, 4, or 8) to the skin for 8 hours. Plasma samples were assayed using sensitive and selective gas-chromatographic methods. For the 8-patch group, the average maximum plasma concentrations (Cmax ± SD) were 41.0 ±5.8 ng/mL, 31.9 ± 8.8 ng/mL, and 29.5 ± 10.5 ng/mL for camphor, menthol, and methyl salicylate, respectively. The corresponding values for the 4-patch group were 26.8 ± 7.2 ng/mL, 19.0 ±5.4 ng/mL, and 16.8 ± 6.8 ng/mL. The harmonic mean terminal half-lives were 5.6 ± 1.3 hours, 4.7 ± 1.6 hours, and 3.0 ± 1.2 hours for camphor, menthol, and methyl salicylate, respectively. The 2-patch group had measurable but low plasma concentrations of each compound. Low-dose dermal application for an extended time results in low plasma concentrations of all 3 compounds. Four and 8 patches, when applied for 8 hours, gave measurable and nearly proportional plasma concentrations. Although unable to determine the absolute dermal bioavailability of these compounds, there appears to be relatively low systemic exposure to these potentially toxic compounds, even when an unrealistically large number of patches are applied for an unusually long time.
KW - Absorption
KW - Camphor
KW - Dermal patches
KW - Menthol
KW - Methyl salicylate
KW - Toxicity
UR - http://www.scopus.com/inward/record.url?scp=4444265322&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=4444265322&partnerID=8YFLogxK
U2 - 10.1177/0091270004268409
DO - 10.1177/0091270004268409
M3 - Article
C2 - 15342616
AN - SCOPUS:4444265322
VL - 44
SP - 1151
EP - 1157
JO - Journal of Clinical Pharmacology
JF - Journal of Clinical Pharmacology
SN - 0091-2700
IS - 10
ER -