Assessment of Drug Delivery Kinetics to Epidermal Targets In Vivo.

It has proven challenging to quantify 'drug input' from a formulation to the viable skin because the epidermal and dermal targets of topically applied drugs are difficult, if not impossible, to access in vivo. Defining the drug input function to the viable skin with a straightforward and practical experimental approach would enable a key component of dermal pharmacokinetics to be characterised. It has been hypothesised that measuring drug uptake into and clearance from the stratum corneum (SC) by tape-stripping allows estimation of a topical drug's input function into the viable tissue. This study aimed to test this idea by determining the input of nicotine and lidocaine into the viable skin, following the application of commercialised transdermal patches to healthy human volunteers. The known input rates of these delivery systems were used to validate and assess the results from the tape-stripping protocol. The drug input rates from in vivo tape-stripping agreed well with the claimed delivery rates of the patches. The experimental approach was then used to determine the input of lidocaine from a marketed cream, a typical topical product for which the amount of drug absorbed has not been well-characterised. A significantly higher delivery of lidocaine from the cream than from the patch was found. The different input rates between drugs and formulations in vivo were confirmed qualitatively and quantitatively in vitro in conventional diffusion cells using dermatomed abdominal pig skin.

Self-reported clinical pharmacy service provision in Austria: an analysis of both the community and hospital pharmacy sector-a national study.

Background With expansion of more advanced clinical roles for pharmacists we need to be mindful that the extent to which clinical pharmacy services are implemented varies from one country to another. To date no comprehensive assessment of number and types of services provided by either community or hospital pharmacies in Austria exists. Objective To analyse and describe the number and types of clinical pharmacy services provided in both community and hospital pharmacies, as well as the level of clinical pharmacy education of pharmacists across Austria. Setting Austrian community and hospital pharmacies. Method An electronic questionnaire to determine number and types of clinical pharmacy services provided was send to all chief pharmacists at all community (n = 1365) and hospital pharmacies (n = 40) across Austria. Besides current and future services provision, education and training provision were also assessed. Main outcome measure Extent of and attitude towards CPS in Austria. Results Response rates to the surveys were 19.1% (n = 261/1365) in community and 92.5% (n = 37/40) in hospital pharmacies. 59.0% and 89.2% of community and hospital pharmacies, respectively, indicated that the provision of clinical pharmacy services in Austria has increased substantially over the past 10 years. Fifty-one percent of community pharmacies reported to provide a medication review service, while 97.3% of hospitals provide a range of services. Only 18.0% of community pharmacies offer services other than medication review services at dispensing. Binary regressions show that provision of already established medication management is a predictor for the willingness of community pharmacists to extend the range of CPS (p < 0.01), while completed training in the area of clinical pharmacy is not (p > 0.05). More hospital than community pharmacists have postgraduate education in clinical pharmacy (17.4% vs 6.5%). A desire to complete postgraduate education was shown by 28.3% of community and 14.7% of hospital pharmacists. Lack of time, inadequate remuneration, lack of resources and poor relationship between pharmacists and physicians were highlighted as barriers. Conclusion Both community and hospital pharmacists show strong willingness to expand their service provision and will need continued support, such as improved legislative structures, more supportive resources and practice focused training opportunities, to further these services.

Corneocyte quantification by NIR densitometry and UV/Vis spectroscopy for human and porcine skin and the role of skin cleaning procedures.

Optical methods of corneocyte quantification during tape stripping experiments on the skin are useful tools for the rapid evaluation of the skin penetration potential of dermally applied substances. However, a comparative investigation of the different methods proposed for this task, namely NIR densitometry and UV/Vis spectroscopy, is still missing. Thus, the aim of the present work was to employ these two techniques in comparative tape stripping experiments both in vivo on human forearm skin and in vitro on porcine ear skin. Standard tape stripping experiments were performed in the absence and presence of a marketed formulation containing flufenamic acid as a model drug. In the context of these methodological investigations, different methods of skin cleaning prior to the tape stripping procedure were evaluated to identify the most appropriate working protocol among the approaches proposed in the respective literature. The results showed that the investigated methods of NIR densitometry and UV/Vis spectroscopy deliver highly comparable results. Both optical methods are suitable to determine the skin penetration profiles of active substances during in vivo and in vitro tape stripping, especially if a simple working protocol without any cleaning procedures is maintained.