The barrier function of the skin in relation to percutaneous absorption of drugs

Wiechers, Johann W.

doi:10.1007/bf01959410

Cited by 144 publications

(94 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Skin barrier function can be ascribed to the macroscopic structure of the stratum corneum, consisting of alternating lipoidal and hydrophylic regions. For this reason, physico-chemical characteristics of the chemical, such as partition coefficient, structure, and molecular weight, play an important role in determining the facility of absorption (8,9). Another factor to consider in drug percutaneous absorption is the vehicle in which the drug is formulated, as it influences drug release from the formulation (7,10).…”

mentioning

confidence: 99%

Occlusion vs. skin barrier function

Zhai

Maibach

2002

Skin Research and Technology

168

View full text Add to dashboard Cite

Background/aims: Skin occlusion may increase percutaneous absorption of applied chemicals, with some exceptions. It also obstructs the normal ventilation of the skin surface and increases stratum corneum hydration and hence compromises skin barrier function. Methods/results: This review focuses the effects of occlusion on skin barrier function, in particularly, as defined with objective skin bioengineering technology. Conclusions: The effects of occlusion on skin barrier function have been defined with various techniques. Optimal hydrocolloid materials can absorb excess water and reduce the unfavourable effects of occlusion.

show abstract

mentioning

confidence: 99%

Occlusion vs. skin barrier function

Zhai

Maibach

2002

Skin Research and Technology

168

View full text Add to dashboard Cite

show abstract

“…On the other hand, the nonpolar enhancer Azone s exerts its action on the hydrophobic tails of the bilayer by upsetting their packing and increasing their fluidity (Wiechers, 1989). …”

Section: Discussionmentioning

confidence: 99%

“…The use of enhancers like azacycloalkane derivatives augments PpIX production, especially in the case of He-ALA ( Van der Akker et al, 2000a). Dimethylsulphoxide (DMSO), which also acts as a penetration enhancer, among other amphiphilic molecules penetrates skin well, probably because the electron-rich part of the molecule has affinity for the aqueous layers of the stratum corneum while the electron-poor portion prefers the lipid region (Wiechers, 1989).…”

mentioning

confidence: 99%

Topical application of ALA and ALA hexyl ester on a subcutaneous murine mammary adenocarcinoma: tissue distribution

et al. 2003

View full text Add to dashboard Cite

Although 5-aminolevulinic acid (ALA)-based photodynamic therapy (PDT) has proven to be clinically beneficial for the treatment of certain cancers, including a variety of skin cancers, optimal tissue localisation still remains a problem. An approach to improve the bioavailability of protoporphyrin IX (PpIX) is the use of ALA derivatives instead of ALA. In this work, we employed a subcutaneous murine mammary adenocarcinoma to study the tissue distribution pattern of the ALA hexyl ester (He-ALA) in comparison with ALA after their topical application in different vehicles. He-ALA induced porphyrin synthesis in the skin overlying the tumour (SOT), but it did not reach the tumour tissue as efficiently. Only 5 h after He-ALA lotion application, tumour porphyrin levels surpassed control values. He-ALA delivered in cream induced a substantially lower porphyrin synthesis in SOT, reinforcing the importance of the vehicle in the use of topical PDT. Porphyrin levels in internal organs remained almost within control values when He-ALA was employed. The addition of DMSO to ALA formulation slightly increased tumour and SOT porphyrin biosynthesis, but it did not when added to He-ALA lotion.

show abstract

“…These results are in agreement with the findings reported earlier (21,22). Upon statistical evaluation (two-way ANOVA), a significant difference was observed between the test products (p < 0.01) but not within the test products for AUC (0)(1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12) , AUC (0-24) , AUC (0-∞) , t 1/2, K el and MRT values. Spearman rank correlation, a non-parametric statistical test, demonstrated a high degree of positive correlation, showing complete agreement in the order of ranks between the percentage of drug absorbed from patches and C max (p < 0.02; two tails), AUC (0-24) (p < 0.02; two tails) and AUC (0-∞) (p < 0.02; two tails).…”

Section: In Vivo Studies In Rabbitsmentioning

confidence: 95%

Development of matrix controlled transdermal delivery systems of pentazocine: In vitro/in vivo performance

Verma

Chandak²

2009

Acta Pharmaceutica

View full text Add to dashboard Cite

Transdermal drug delivery system is being extensively investigated as a viable alternative to drug delivery with improved bioavailability. It offers many advantages over conventional administration such as enhanced efficacy, increased safety, and greater convenience and improved patient compliance. Transdermal route permits the use of a relatively potent drug with minimal risk of systemic toxicity and avoids gastrointestinal degradation and hepatic first-pass metabolism (1-3). A number of therapeutic agents, including antihypertensive, antianginal, antihistaminic, anti-inflammatory, analgesic, The present study aimed to develop hydroxypropyl methylcellulose based transdermal delivery of pentazocine.In formulations containing lower proportions of polymer, the drug released followed the Higuchi kinetics while, with an increase in polymer content, it followed the zero-order release kinetics. Release exponent (n) values imply that the release of pentazocine from matrices was non-Fickian. FT-IR, DSC and XRD studies indicated no interaction between drug and polymer. The in vitro dissolution rate constant, dissolution half-life and pharmacokinetic parameters (C max , t max , AUC (s) , t 1/2, K el , and MRT) were evaluated statistically by two-way ANOVA. A significant difference was observed between but not within the tested products. Statistically, a good correlation was found between per cent of drug absorbed from patches vs. C max and AUC (s) . A good correlation was also observed when per cent drug released was correlated with the blood drug concentration obtained at the same time point. The results of this study indicate that the polymeric matrix films of pentazocine hold potential for transdermal drug delivery.Keywords: pentazocine, transdermal drug delivery, Cygnus' sandwich patch holder, in vitro characterization, in vivo evaluation * Correspondence; e-mail: prpverma275730@yahoo.com Unauthenticated Download Date | 8/28/18 7:56 PM and anti-arthritic drugs, are being investigated and developed for the transdermal therapeutic system either for academic research or for commercial purposes (3, 4). The present work is aimed at developing a matrix-dispersion type transdermal drug delivery of pentazocine.Pentazocine (PTZ), a benzomorphan derivative, is an opioid analgesic that has mixed opioid agonist and antagonist actions. It is considered to be a partial agonist or weak antagonist at the m-receptor and a k-receptor agonist. Pentazocine is used for relief of moderate to severe pain. Oral administration of PTZ has the disadvantage of low bioavailability (about 18-22 %) due to extensive first-pass metabolism (5-7). In addition, PTZ has a short half-life of 2-4 h and requires frequent dosing in order to maintain the optimal therapeutic concentration. Repeated injections over long periods may cause fibrotic changes in the skin and muscular tissue. Low molecular mass (285.4), suitable pK a values of 8.5 and 10, log P (octanol/phosphate buffer pH 7.4) of 2.0 and low oral bioavailability provide a rationale for developing a...

show abstract

The barrier function of the skin in relation to percutaneous absorption of drugs

Cited by 144 publications

References 49 publications

Occlusion vs. skin barrier function

Occlusion vs. skin barrier function

Topical application of ALA and ALA hexyl ester on a subcutaneous murine mammary adenocarcinoma: tissue distribution

Development of matrix controlled transdermal delivery systems of pentazocine: In vitro/in vivo performance

Contact Info

Product

Resources

About