review on bioadhesive buccal drug delivery systems: current status of formulation and evaluation methods

Owing to the ease of the administration, the oral cavity is an attractive site for the delivery of drugs. Through this route it is possible to realize mucosal [local effect] and transmucosal [systemic effect] drug administration. In the first case, the aim is to achieve a site-specific release of the drug on the mucosa, whereas the second case involves drug absorption through the mucosal barrier to reach the systemic circulation. The main obstacles that drugs meet when administered via the buccal route derive from the limited absorption area and the barrier properties of the mucosa. The effective physiological removal mechanisms of the oral cavity that take the formulation away from the absorption site are the other obstacles that have to be considered. The strategies studied to overcome such obstacles include the employment of new materials that, possibly, combine mucoadhesive, enzyme inhibitory and penetration enhancer properties and the design of innovative drug delivery systems which, besides improving patient compliance, favor a more intimate contact of the drug with the absorption mucosa. This presents a brief description of advantages and limitations of buccal drug delivery and the anatomical structure of oral mucosa, mechanisms of drug permeation followed by current formulation design in line with developments in buccal delivery systems and methodology in evaluating buccal formulations

Effect of pomegranate pretreatment on the oral bioavailability of buspirone in male albino rabbits

Many drug substances and variety of naturally occurring dietary or herbal components are capable of interaction with the CYP enzyme system. The aim of the study was to investigate the effect of pomegranate juice pretreatment on the bioavailability of buspirone in rabbits. White New Zealand rabbits weighing 2.1 +/- 0.13 Kg were selected for study. The bioavailability of buspirone after pre-treatment with pomegranate juice [10 ml Kg-1 for seven days] was compared with an oral solution of 10 mg kg-1 of buspirone in distilled water. Animals were allowed free access to food and water, until night prior to dosing and were fasted for 10 hrs. In the first phase oral solution [10 mg kg-1] was administered through feeding tube followed by rinsing with 10 ml of water. In the second phase, the group was pretreated with pomegranate juice for 7 days and study was conducted after 15 days of washout period. The results showed that there was a significant [p<0.05] difference in the bioavailability of buspirone after pre-treatment with pomegranate juice. This increase in bioavailability might be due to inhibition of CYP3A4. Further studies are required to prove this mechanism in humans

Effect of pomegranate juice pre-treatment on the transport of carbamazepine across rat intestine

Many drug substances along with a variety of naturally occurring dietary or herbal components interact with the CYP enzyme system. The present study was aimed to investigate the effect of pomegranate juice pre-treatment on the transport of carbamazepine across the rat intestine. The transport of carbamazepine across different parts of rat intestine was studied by everted and non-everted sac methods. The control and pomegranate juice [10 ml Kg[-1] for 7 days] pre-treated rats were sacrificed and isolated the intestine. The sacs of intestine were prepared, treated with carbamazepine solution and then placed in dulbeccos buffer. Samples were collected periodically and the drug content was estimated using HPLC. Results and The results show that there was a significant [p<0.05] difference in the transport of carbamazepine from the intestinal sacs of pretreated with pomegranate juice and control. It seems that pomegranate juice might have induced CYP3A4 enzymes and hence drug is extensively metabolized