BBG
01-14-2013, 02:38 PM
When applying transdermal products, two very important variables are under your full control:
-Site of application
-Surface area of application
The thicker the stratum corneum at the site of application, the less flux you'll achieve & the longer it'll take to notice any effects. As it turns out, the thickness of the SC is highly variable across different areas of the body. This is not due to differences in SC cell size, but to differences in the number of SC cell layers. (The individual cells of the SC are generally uniform in size.) Keeping that in mind, a Japanese study (Z. Ya-Xian, 1999) measured the number of SC cell layers at many points, in hundreds of subjects. Their results were:
Genitals: 6 ± 2 (number of SC cell layers ± standard deviation.)
Face: 9 ± 2
Neck: 10 ± 2
Scalp: 12 ± 2
Trunk: 13 ± 4
Limbs: 15 ± 4
Palms and soles: 47 ± 24
Heels: 86 ± 36
...Which are in general agreement with other observations. Holbrook and Odland, in 1971, measured SC thickness at four sites:
Back: 9.4 µm (mean thickness)
Abdomen: 8.2 µm
Forearm: 12.9 µm (note: The forearm is not a very good application spot!)
Thigh: 10.9 µm
Rougier et al., in a paper published in the book "Transdermal Absorption of Dermatological Products", measured the percutaneous absorption of benzoic acid at 11 different sites. Their results are in the image [see in link], and can be summarized: Forehead > postauricular (neck behind ear) > > > everything else.
If your skin isn't overly-sensitive, I would therefore recommend application to the postauricular/neck/clavicle region -- rotating to the shoulder and upper-chest every other day for skin-safety's sake. Any transdermal products you use will be markedly more effective if you take care to apply 'em to those spots with low stratum corneum thickness.
(Please do not apply to your face or genitals, though. Your skin in those areas contains lots of sensitive nerve-endings, and most transdermals, including Trenazone, contain harsh solvents which may cause pain or discomfort.)
The second variable I mentioned earlier is of equal importance: Transdermal flux is usually measured in µg/cm²/hour, so the more square centimeters you spread your dose over, the more flux you'll achieve. (This may be why subsaturated solutions which call for dosing protocols of 2+ml/day seem to be more effective for some than saturated solutions which call for 1ml/day or less; even if the difference in flux may be 5µg/cm²/hr vs. 10µg/cm²/hour, the fact that the former is spread over many more square centimeters should lead to greater total flux.)
So... spread your transdermals as thinly and as broadly as possible. I know that it can be a hassle with Trenazone's 1ml dose, but it will really make a big difference.
...Thank you very much for the support, by the way.
-Jake
From the Antaeus Labs Blog
-Site of application
-Surface area of application
The thicker the stratum corneum at the site of application, the less flux you'll achieve & the longer it'll take to notice any effects. As it turns out, the thickness of the SC is highly variable across different areas of the body. This is not due to differences in SC cell size, but to differences in the number of SC cell layers. (The individual cells of the SC are generally uniform in size.) Keeping that in mind, a Japanese study (Z. Ya-Xian, 1999) measured the number of SC cell layers at many points, in hundreds of subjects. Their results were:
Genitals: 6 ± 2 (number of SC cell layers ± standard deviation.)
Face: 9 ± 2
Neck: 10 ± 2
Scalp: 12 ± 2
Trunk: 13 ± 4
Limbs: 15 ± 4
Palms and soles: 47 ± 24
Heels: 86 ± 36
...Which are in general agreement with other observations. Holbrook and Odland, in 1971, measured SC thickness at four sites:
Back: 9.4 µm (mean thickness)
Abdomen: 8.2 µm
Forearm: 12.9 µm (note: The forearm is not a very good application spot!)
Thigh: 10.9 µm
Rougier et al., in a paper published in the book "Transdermal Absorption of Dermatological Products", measured the percutaneous absorption of benzoic acid at 11 different sites. Their results are in the image [see in link], and can be summarized: Forehead > postauricular (neck behind ear) > > > everything else.
If your skin isn't overly-sensitive, I would therefore recommend application to the postauricular/neck/clavicle region -- rotating to the shoulder and upper-chest every other day for skin-safety's sake. Any transdermal products you use will be markedly more effective if you take care to apply 'em to those spots with low stratum corneum thickness.
(Please do not apply to your face or genitals, though. Your skin in those areas contains lots of sensitive nerve-endings, and most transdermals, including Trenazone, contain harsh solvents which may cause pain or discomfort.)
The second variable I mentioned earlier is of equal importance: Transdermal flux is usually measured in µg/cm²/hour, so the more square centimeters you spread your dose over, the more flux you'll achieve. (This may be why subsaturated solutions which call for dosing protocols of 2+ml/day seem to be more effective for some than saturated solutions which call for 1ml/day or less; even if the difference in flux may be 5µg/cm²/hr vs. 10µg/cm²/hour, the fact that the former is spread over many more square centimeters should lead to greater total flux.)
So... spread your transdermals as thinly and as broadly as possible. I know that it can be a hassle with Trenazone's 1ml dose, but it will really make a big difference.
...Thank you very much for the support, by the way.
-Jake
From the Antaeus Labs Blog