Rose geranium essential oil as a source of new and safe anti-inflammatory drugs

Background: Since the available anti-inflammatory drugs exert an extensive variety of side effects, the search for new anti-inflammatory agents has been a priority of pharmaceutical industries. Aims: The aim of the present study was to assess the anti-inflammatory activities of the essential oil of rose geranium (RGEO). Methods: The chemical composition of the RGEO was investigated by gas chromatography. The major components were citronellol (29.13%), geraniol (12.62%), and citronellyl formate (8.06%). In the carrageenan-induced paw edema, five different groups were established and RGEO was administered orally in three different doses. Results: RGEO (100 mg/kg) was able to significantly reduce the paw edema with a comparable effect to that observed with diclofenac, the positive control. In addition, RGEO showed a potent anti-inflammatory activity by topical treatment in the method of croton oil-induced ear edema. When the dose was 5 or 10 mu l of RGEO per ear, the inflammation was reduced by 73 and 88%, respectively. This is the first report to demonstrate a significant anti-inflammatory activity of Algerian RGEO. In addition, histological analysis confirmed that RGEO inhibited the inflammatory responses in the skin. Conclusion: Our results indicate that RGEO may have significant potential for the development of novel anti-inflammatory drugs with improved safety profile.