Effect of Hydroalcoholic Extract of Hyssop on Acute Pain in Male Rats Using Tail Flick Test

Iranian traditional medicine uses hyssop (Hyssopus officinalis) as an effective medicinal plant to reduce pain and inflammation in different diseases. Although the anti-inflammatory effect of this plant is proved, there is no study into its analgesic effects. Thus, this study aimed to investigate the analgesic effect of the hydroalcoholic extract from hyssop flowers and upper branches.

This experimental study was conducted on 66 male rats that were divided into several groups including a saline control group, the groups of different doses of hyssop extract, morphine positive control group, the groups of hyssop extract plus morphine, and the most effective dose of the hyssop extract plus naloxone. All injections were administered intraperitoneally, and the pain was measured through the tail flick test.

Based on the results, 600 mg/kg was the most effective analgesic hyssop extract dose, and the most analgesic effect was observed at 45 minutes after administration. In addition, the administration of the most effective extract dose (600 mg/kg) plus morphine significantly improved the analgesic effects of morphine (P<0.001). Finally, the administration of naloxone plus the most effective extract dose (600 mg/kg) significantly reduced the analgesic effect of the extract (P<0.05).

Overall, the hydroalcoholic extract of hyssop has analgesic effects that are probably applied through opioid receptors.