Evaluation and comparison of anti-inflammatory properties of ibuprofen using two drug delivery systems after third molar surgery: using chitosan microspheres as a carrier for local drug delivery in to the third molar socket and through the oral route

Considerable research efforts have been directed towards developing safe and efficient chitosan-based particulate drug delivery systems. The present review outlines the major new findings on the pharmaceutical applications of chitosan-based micro/nanoparticulate drug delivery systems published over the past decade. Methods of their preparation, drug loading, release characteristics, and applications are covered. Chemically modified chitosan or its derivatives used in drug delivery research are discussed critically to evaluate the usefulness of these systems in delivering the bioactive molecules. From a literature survey, it is realized that research activities on chitosan micro/nanoparticulate systems containing various drugs for different therapeutic applications have increased at the rapid rate. Hence, the present review is timely.

Chitosan and its half-acetylated derivative have been compared as excipients in mucoadhesive tablets containing ibuprofen. Initially the powder formulations containing the polymers and the drug were prepared by either co-spray drying or physical co-grinding. Polymer-drug interactions and the degree of drug crystallinity in these formulations were assessed by infrared spectroscopy and differential scanning calorimetry. Tablets were prepared and their swelling and dissolution properties were studied in media of various pHs. Mucoadhesive properties of ibuprofen-loaded and drug-free tablets were evaluated by analysing their detachment from pig gastric mucosa over a range of pHs. Greater polymer-drug interactions were seen for spray-dried particles compared to co-ground samples and drug loading into chitosan-based microparticles (41%) was greater than the corresponding half-acetylated samples (32%). Swelling and drug release was greater with the half-acetylated chitosan tablets than tablets containing the parent polymer and both tablets were mucoadhesive, the extent of which was dependent on substrate pH. The results illustrate the potential sustained drug delivery benefits of both chitosan and its half-acetylated derivative as mucoadhesive tablet excipients.

We conducted a randomised double-blind placebo-controlled single-centre study to compare the effect of preoperative ibuprofen 600 mg, diclofenac 100 mg, paracetamol 1 g with codeine 60 mg or placebo (Vitamin C 50 mg) tablets for relief of postoperative pain in 119 patients who had day case operations under general anaesthesia for removal of impacted third molars. Patients were given the tablets 1 h before operation. Pain was assessed using visual analogue scales and verbal rating scales preoperatively at 15 and 30 min and 1 and 3 h postoperatively. After they had gone home, patients were contacted by telephone at 6 and 24 h postoperatively to find out whether they had any adverse effects from the analgesics. There was no significant difference in the extent of postoperative pain among the four groups, but the placebo group had significantly shorter times before their first request for postoperative analgesics (median 17 min, range 14-90) than the diclofenac group (median 32, range 15-150). Preoperative analgesics at the stated doses are effective in providing immediate postoperative pain control after operations on third molars. There were, however, some side-effects including nausea, vomiting, headaches, and gastrointestinal discomfort, but there were no significant differences among the active analgesic groups with respect to adverse events either shortly after operation or at 6 or 24 h.