ethyl-cellulose and Pain

To develop a film formulation allowing controlled release for long-term analgesia, we selected ethyl cellulose (EC) as a novel additive, prepared a film formulation using indomethacin (IM film), and evaluated it in vitro and clinically. In the in vitro experiments, the effects of the EC concentration on the release rate of IM and on the adhesion force to the mucous membrane were investigated. The addition of 10% EC resulted in more sustained slow release compared with no EC, and the adhesion of the film with 10% EC added was similar to that of films containing carboxyvinyl polymer, which we reported previously showed significantly increased adhesion. A two-layered film consisting of an adhesive layer with 2% or 1% IM and 10% EC and a nonadhesive layer with 2% polyethylene glycol as a softening agent, was investigated for clinical use. Film consisting of an adhesive layer with 2% IM and 10% EC exhibited rapid onset of potent analgesia and was expected to prolong the duration of analgesia. These results suggest that IM film with EC added may be useful clinically, since it shows both immediate analgesic effects and prolonged duration of release.

Topics: Adhesiveness; Adjuvants, Pharmaceutic; Adult; Aged; Aged, 80 and over; Anti-Inflammatory Agents, Non-Steroidal; Cellulose; Chemistry, Pharmaceutical; Chemistry, Physical; Delayed-Action Preparations; Dosage Forms; Drug Stability; Female; Humans; Indomethacin; Male; Middle Aged; Mouth Mucosa; Pain; Young Adult

The present work aimed at the DIM-loaded microparticles development and anti-hypernociceptive action evaluation.. The formulations were prepared by O/W solvent emulsion-evaporation method and characterised by particle diameter, content and DIM encapsulation efficiency, drug release profile, thermal behaviour and physicochemical state. The anti-hypernociceptive action was evaluated in the animal model of acute inflammatory pain.. The MPs had a mean diameter in the micrometric range (368 ± 31 μm), narrow size distribution, DIM content of 150 mg/g, encapsulation efficiency around 84% and prolonged compound release. Evaluations of the association form of DIM to MPs demonstrated the feasibility of the systems to incorporate DIM and increases its thermal stability. An improvement in the anti-hypernociceptive action of DIM was observed by its microencapsuation, because it was increased and prolonged.. Therefore, the MPs developed represent a promising formulation for oral administration of the DIM in the treatment of inflammatory pain.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Capsules; Cellulose; Drug Carriers; Indoles; Male; Mice; Pain