The purpose of this study was to demonstrate that the phenomenon induced by mixing powder components at an ultrahigh speed could be directly applicable to the preparation of drycoated particles with a controlled-release property. In particular, we tried to prepare controlled-release particles that were dry-coated on microcrystalline cellulose particles (CP-203) as a core particle.

The controlled-release coating agents, hydrogenated castor oil (HCO) and polyethylene glycol (PEG), formed a matrix layer with dispersed theophylline (TP) as a model drug on CP-203 by mixing the dry components at an ultrahigh-speed. By this method, single controlled-release particles could be produced. Dissolution of TP from the particles was controllable by regulating the initial mass ratio of CP-203, TP, HCO, and PEG. The new method showed high reproducibility in terms of the particle product characteristics, with no need for pre-mixing of the components.

In conclusion, this study shows that a simple preparation of controlled-release particles has been achieved using a new dry-coating method, without organic solvents or water. The single, coated particles obtained show promise as a basic component for manufacturing multiple-unit type formulations consisting of controlled-release particles.

As-needed use of Lorazepam (LOR) by patients with psychiatric maladies is described as effective when they show an unexpected restlessness. In this study, we attempted to prepare a sublingual film containing LOR (LOR-film) to improve both the instantaneous effect of LOR and the convenience of drug administration. Polyglutamic acid (γ-PGA), hydroxypropyl starch (HPS) and its resolvent were adopted as the main ingredients in the film, and various amount of glycerol (Gly) and/or glycerin fatty acid ester (GE) were added as plasticizer or surfactant. While the increase in the amount of Gly added increased the adhesion property and plasticity of the film, there had been a tendency to decrease the disintegration time and handling ability. As for the release of LOR from LOR-film, a tendency to delay was recognized with an increase in the amount of Gly. On the other hand, an increase in the amount of GE accelerated the release of LOR at the initial portion. Disintegration time of LOR-films in the oral cavity was prolonged with an increase in an increase of the amount of Gly. These results indicate that the release of LOR from LOR-film is controllable by the amount of Gly or GE.

Topical retinoids are very important in acne treatments. Clinical experience has shown that adapalene, a new topical retinoid, has a superior cutaneous safety profile. In the guidelines of care for acne vulgaris management of our country, the combinations with adapalene gel and topical antibiotics (e.g., clindamycin nadifloxacin) are an effective acne treatment, and these combination treatments are ranked as a recommendation A. For the purpose of improvement of compliance, the mixing of ointments and/or creams is common practice. However, many of the admixtures of ointments and/or creams may lack pharmaceutical stability.

To assess the pharmaceutical stability of these mixtures after mixing, we attempted to investigate the change in the appearance and contents of adapalene, clindamycin and nadifloxacin in admixtures. As a result, no lowering of the content of adapalene was noted in any admixtute. After admixtures of adapalene and clindamycin or nadifloxacin, the contents of clindamycin or nadifloxacin were constant.