Evaluation of analgesic and anti-inflammatory effects of fresh onion juice in experimental animals

Abstract

Onion is a well known traditional medicinal plant that has been consumed for its putative nutritional and health benefits for centuries. This study was carried out to determine the possible analgesic and anti-inflammatory effects of fresh onion juice in experimental animals. Hot plate and formalin tests were used to study the analgesic effect of fresh onion juice in mice during acute and chronic pain stages modeling, respectively. The anti-inflammatory effect of fresh onion juice was assessed by applying carrageenan sub plantar injection to Sprague-Dawley rats. The obtained results illustrated a significant analgesic property for fresh onion juice in both pain phases compared with positive control group (Pv≤0.05); the effects were similar to that of morphine (5 mg/kg) as the standard treatment. In inflammation assessment, fresh onion juice was able to decrease the hind paw thickness significantly in comparison with control group (Pv≤0.001). In the mean time, it also demonstrated better results than the standard treatment, diclofenac with a 10 mg/kg dosage, (Pv≤0.05). It can be concluded that fresh juice of onion is capable of inhibiting both acute and chronic pain as well as inflammation, with a more strong effect towards inflammation. Key words: Allium cepa, analgesic, anti-inflammatory, hot plate test, formalin test, carrageenan test.