Background & Objective: Several studies have shown that Soya oil has analgesic effects when it administered orally or injected. Oral administration of Soya oil has antinociceptive effect on bone dysplasia induced pain. Based on previous reports concerning analgesic effect of peripheral administration of Soya oil and the usage of the oil as a solvent or the oil part of emulsions to prepare water-insoluble drugs, we investigated the analgesic effect of intracerebroventricular (i.c.v.) injection of Soya oil.
Materials & Methods: The antinociceptive effects of i.c.v. administration of Soya oil using formalin test have been studied in stereotaxed mice after one week of surgery and insertion of a stainless steel canulla in the right cerebroventricle.
Results: Administration of pure Soya oil induced an antinociceptive effect in mice but the oil did not show any analgesic effects in 10 percent concentration.
Conclusion: The results of this study are in agreement with previous data on analgesic effect of peripheral administration of Soya oil. Therefore, we suggest that minimum concentrations should be used to prepare emulsions with Soya oil for water insoluble drugs in antinociception studies.