Dermal preparations emulsions

Dermal preparations solutions, suspensions and emulsions for cutaneous use, shampoos... 

Also linalool alone, one of the most prominent monoterpene alcohols, is used in many dermal preparations as penetration enhancer. In a series of in vitro studies it was shown that linalool enhanced its own penetration (Cal and Sznitowska, 2003) as well as the absorption of other therapeutics, such as haloperidol (Vaddi et al., 2002a, 2002b), metoperidol (Komuru et al., 1999), propa-nolol hydrochloride (Kunta et al, 1997), and transcutol (Ceschel et al., 2000). Cal (2005) showed in another in vitro stndy the influence of linalool on the absorption and elimination kinetics and was able to prove that this monoterpene alcohol furnished the highest absorption ratio compared to an oily solution or an 0/W emulsion. 

In the chemical industry (on the mega- as well as the micro-scale) fine emulsions have many useful applications in, e.g., extraction processes or phase transfer catalysis. Additionally, they are of interest for the pharmaceutical and cosmetic industry for the preparation of creams and ointments. Micromixers based on the principle of multilamination have been found to be particularly suitable for the generation of emulsions with narrow size distributions [33]. Haverkamp et al. showed the use of micromixers for the production of fine emulsions with well-defined droplet diameters for dermal applications [38]. Bayer et al. [39] reported on a study of silicon oil and water emulsion in micromixers and compared the results with those obtained in a stirred tank. They found similar droplet size distributions for both systems. However, the specific energy required to achieve a certain Sauter mean diameter was 3-1 Ox larger for the macrotool at diameters exceeding 100 pm. In addition, the micromixer was able to produce distributions with a mean as low as 3 pm, whereas the turbine stirrer ended up with around 30 pm. Based on energy considerations, the intensification factor for the microstirrer appears to be 3-10. 

Liquid preparations for cutaneous application are described as preparations with variable viscosity intended for local or transdermal application. This category comprises solutions, emulsions and suspensions for dermal use containing rnie or more active substances in a suitable base. As examples for liquid preparations shampoos and cutaneous foams are defined in Ph. Eur. 

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