ethyl-cellulose and Bacterial-Infections

Bearing in mind the present scenario of the increasing biological tolerance of bacteria against antibiotics, a time controlled two pulse dosage form of amoxicillin was developed. The compression coating inlay tablet approach was used to deliver the drug in two pulses to different parts of the GIT after a well defined lag time between the two releases. This was made possible by formulating a core containing one of the two drug fractions (intended to be delivered as the second pulse), which was spray coated with a suspension of ethyl cellulose and a hydrophilic but water insoluble agent as a pore former (microcrystalline cellulose). Coating of up to 5% (m/m) was applied over the core tablet, giving a corresponding lag of 3, 5, 7 and 12 h. Increasing the level of coating led to retardation of the water uptake capacity of the core, leading to prolongation of the lag time. Microcrystalline cellulose was used as a hydrophilic but water insoluble porosity modifier in the barrier layer, varying the concentration of which had a significant effect on shortening or prolongation of the lag time. This coated system was further partially compression coated with the remaining drug fraction (to be released as the first immediate release pulse) with a disintegrant, giving a final tablet. The core tablet and the final two pulse inlay tablet were further investigated for their in vitro performance.

Topics: Administration, Oral; Amoxicillin; Anti-Bacterial Agents; Bacterial Infections; Cellulose; Delayed-Action Preparations; Dose-Response Relationship, Drug; Drug Chronotherapy; Drug Compounding; Drug Delivery Systems; Drug Resistance, Microbial; Excipients; Gastrointestinal Tract; Humans; Pressure; Solubility; Tablets; Tablets, Enteric-Coated; Time Factors; Viscosity

Toothache is a serious problem worldwide. To give relief from this intolerable toothache, doctors prescribe painkillers along with antibiotics. Most of the painkillers, if not all, produce hyperacidity and gastric irritation upon oral administration. Oral antibiotics have slow onset of action and undergo hepatic "first-pass" effect. Moreover, available dental formulations are mostly liquid and last only few hours upon application, before being washed out by saliva. To overcome the above-mentioned problems, a soft polymeric mold containing antibiotic and analgesic drugs and having an appropriate consistency to adhere to the tooth, was developed for sustained drug release to provide better relief in dental patients. Eudragit L 100-55, carbopol 971 P, gum karaya powder and ethyl cellulose were used to prepare the mold "Denticaps" containing Lidocaine hydrochloride and Amoxicillin trihydrate individually and in combination, by mixing and solvent evaporation technique. Different physicochemical characterization studies such as mucoadhesion test, water absorption capacity and swelling index were carried out. In vitro drug release studies showed sustained release of Lidocaine hydrochloride and Amoxicillin trihydrate in simulated saliva for 24 h. Further studies are warranted to succeed with these formulations in humans. Upon success, this type of dosage form may open up new avenues towards dentistry.

Topics: Acrylates; Acrylic Resins; Adhesiveness; Amoxicillin; Anesthetics, Local; Anti-Bacterial Agents; Bacterial Infections; Biological Availability; Calorimetry, Differential Scanning; Cellulose; Delayed-Action Preparations; Drug Delivery Systems; Excipients; Gingival Diseases; Karaya Gum; Lidocaine; Microscopy, Electron, Scanning; Spectroscopy, Fourier Transform Infrared; Surface Properties; Tooth Diseases; Toothache; Water