Clinical Research on the Effects of Differences in Properties of External Preparations for Skin on Application Amount: An Exploratory Investigation of the Relationship between the Base Usability and Application Amount by Questionnaire in Adult Subjects

Abstract

Compared to oral medication, the base plays a large role in the external preparation for skin, and dermatologists select the dosage form based on understanding of the eŠect of the base as well as according to skin symptoms and conditions, application site, age, season, etc. Further, in treatment with external preparations, it is important for patients to understand the application method and continue to apply an adequate amount to achieve the treatment goal. However, there is little evidence regarding the relationship between base properties or usability and the application amount. In this study, we investigated the usability and application amount of three bases with diŠerent properties (ointment base, cream base, and lotion base) in 62 adult subjects and exploratively examined the eŠect of the diŠerent base properties on the application amount. The results of this clinical study showed that the usability and preference for the base used for external preparations varies, and poor usability and low preference may lead to a reduction in the application amount. Even with good usability and high preference, there were many cases in which an adequate amount was not applied due to lack of speciˆc instructions on external use. When selecting or changing the base in an external therapy, it is important for not only dermatologists but also pharmacists providing instructions on external use to be aware of the importance of the base and actively instruct patients to apply an adequate amount of the preparation.

Clinical study on the effects of the applied volume of moisturizer in patients with asteatosis

“…The 1/3 FTU equivalent dose was selected as "a usual dose in clinical practice" because it was considered appropriate by patients who had not received any dosage instructions from their treating clinician. 10 The results after twice daily treatment with the moisturizer showed that the dry symptoms of the skin in the 20,21 In this study, however, the treatment effect of a 2 FTU equivalent dose was not considered as this is considered to be an excessive amount for application, and it will not remain on the skin because a portion of the coating drug attaches to clothes daily life.…”

“…The 1/3 FTU equivalent dose was selected as “a usual dose in clinical practice” because it was considered appropriate by patients who had not received any dosage instructions from their treating clinician. 10 …”

“…We investigated whether the treatment outcomes with the application of moisturizer twice daily were different between the 1 FTU equivalent dose (~ 1.5 g/target lower leg) and 1/3 FTU equivalent dose (~0.5 g/target lower leg) in patients with moderate to severe asteatosis. The 1/3 FTU equivalent dose was selected as “a usual dose in clinical practice” because it was considered appropriate by patients who had not received any dosage instructions from their treating clinician 10 …”

“… 10 Over half of the volunteers did not apply the volume corresponding to 1 FTU equivalent dose, and the applied volume was instead 0.3–0.4 FTU equivalent dose in the case of half. 10 These results suggested that failure to understand appropriate volume instructions among patients would result in lower than intended equivalent doses in clinical practice.…”

Characteristics of an Emulsion Obtained Using Hydrophobic Hydroxypropyl Methylcellulose as an Emulsifier and a High-Pressure Homogenizer

“…Lotion is especially convenient for use on the scalp (or other site with hair), or to cover large areas because it has low viscosity and is easy to spread. 1,2) The main component of lotion is water, and three types of lotion exist: solution, suspension, and emulsion. Drugs with low water solubility are hard to formulate in solution-type lotions without the use of solubilizing solvents/agents and procedures; therefore, emulsion-type lotion is especially attractive for oilsoluble drugs.…”