Most pharmaceutical formulations also include a certain amount of lubricant to improve their flowability and prevent their adhesion to the surfaces of processing equipment. Magnesium stearate is an additive that is most frequently used as a lubricant. Magnesium stearate is capable of forming films on other tablet excipients during prolonged mixing, leading to a prolonged drug liberation time, a decrease in hardness, and an increase in disintegration time. It is hydrophobic, and there are many reports in the literature concerning its adverse effect on dissolution rates. The objective of this study was to evaluate the effects of two different concentrations of magnesium stearate on dissolution properties of ranitidine hydrochloride coated tablet formulations labeled to contain 150 mg. The uniformity content was also checked. During the drug formulation development, several samples were designed for choice of the formulation. For this study, two formulations containing 0,77 and 1,1% of magnesium stearate added in the manufacture of cores were chosen. Fraction of ranitidine hydrochloride released in dissolution medium was calculated from calibration curves. The data were analyzed using pharmacopeial test for similarity of dissolution profiles ( f2 equation), previously proposed by Moore and Flanner. Application of f2 equation showed differences in time-course of ranitidine hydrochloride dissolution properties. The obtained values indicate differences in drug release from analyzed ranitidine hydrochloride formulations and could cause differences in therapeutic response.

In order to achieve the multi-claim products required for the dental care category, it is necessary for the formulator to use a variety of different ingredients. This places a number of demands on the development process. Innovations in the areas of pharmaceutical technology have contributed to the formulation of the products having superior efficacy as well as other attributes that may contribute to clinical response and patient acceptability. Improved clinical efficacy and tolerability, along with conditioning signals, should encourage patient compliance with oral hygiene further complementing professional efforts directed at disease prevention. The most effective way of preventing the development of dental disease is in controlling the production of dental plaque. It is formed by microbial action. The removal of plaque from the teeth and related areas is essential for the maintenance of a healthy mouth. In this paper we have presented the main components of toothpastes and mouthwashes. For the active ingredients, their supposed effect as therapeutic agents is also explained.