[Lotion with hydroquione - tretinoin]. / Lotion a l'hydroquinone et a la trétinoïne.

The observed precipitation in a lotion containing 4% of hydrochinon and 0,03% of tretinoine is evaluated. To dissolve both actives, 10% propyleneglycol is used and the alcohol concentration varied. From the results it is demonstrated that at least 54 ml of ethanol 96 degrees is necessary to dissolve both actives. It is also demonstrated that the addition of 0.2% of vitamin C, as antioxidant, is necessary to avoid coloration of the lotion, as a function of time, due to the presence of hydrochinon.

[Pharmacy compounding of medicinal shampoos: an update]. / Aspects galéniques des shampooings médicinaux: mise a jour.

Delivery of magistral (extemporaneous) preparations must comply with quality standards, as described in the "Guide to Good Officinal Pharmaceutical Practice" and the pharmacy's Quality Manual (Royal Decree of 21 January 2009). In this study, the shampoo Simplex Herdewijn, prepared with Texapon NSO, is compared with commercially available basic shampoos (Shampoo Fagron and Shampoo Simplex Conforma) with respect to its composition as well as its physicochemical properties. These basic shampoos were used to develop medicinal shampoos. The active compounds of these shampoos were: 0.5% hexachlorophene, 1% ichtammol, 1% cade oil or 2% liquor carbonis detergens. The necessary concentration of Cetomacrogol 1000, required to solubilise the active compounds was determined, as well as the amount of sodium chloride needed to adjust the viscosity of the shampoo. The viscosity of the basic and medicinal shampoos was determined by means of rheograms and by calculating their apparent viscosity. Additionally, a number of fundamental aspects of the formulation of shampoos are discussed in this paper. The results can be useful to pharmacists as guidelines for the preparation of medicinal shampoos. Beside patient instruction and pharmaceutical care, the intrinsic quality of magistral preparations is a prerequisite for therapeutic activity.