Study of analgesic effect of naproxen solid dispersions in crosspovidone and Elaeagnus Angustifolia fruit powder by using formalin test

Abstract

Objectives: Naproxen is a poor water soluble non-steroidal analgesic and anti-inflammatory drug. Oral absorption and effectiveness of a drug can be improved by preparing solid dispersions and subsequent increase of dissolution rate. The aim of this study was to evaluate analgesic effect of solid dispersions of naproxen (1:1) in crosspovidone and Elaeagnus Angustifolia fruit powder by using co-grinding technique and formalin test. Methods: Study was carried out in male wistar rats weighing 180-200g (n=8 rats per each group). Formalin test was performed one hour after oral administration of drugs by intraplantar injection of formalin 2.5%. Results: Solid dispersions of naproxen in crosspovidone and Elaeagnus Angustifolia produced more (P<0.001) analgesic effect when compared with physical mixtures of naproxen with crosspovidone and Elaeagnus Angustifolia and pure naproxen powder. The analgesic effect of physical mixtures of naproxen with crosspovidone and Elaeagnus Angustifolia were not significantly different from pure naproxen powder. The analgesic effect of solid dispersion of naproxencrosspovidone was markedly (P<0.01) more than of solid dispersion of naproxen- Elaeagnus Angustifolia. Conclusion: We suggest that the analgesic effect of naproxen may be increased by preparing its solid dispersions in crosspovidone and Elaeagnus Angustifolia fruit powder.