Study Leads New Insights into How Ginkgo May Help to Reduce Postoperative Pain

Newswise — San Francisco, CA. (April 26, 2011) – Experiments in rats show that a standardized ginkgo extract—injected either into the spinal canal or directly into the injured area—effectively reduces inflammation and some types of pain, according to a report in the May issue of Anesthesia & Analgesia, official journal of the International Anesthesia Research Society (IARS).

The ginkgo biloba extract EGb 761 reduces abnormal responses to heat pain (thermal hyperalgesia), with an effect similar to that of a commonly used pain reliever, reports the study by Sharron Dolan, Ph.D., and colleagues of Glasgow Caledonian University, U.K. They write, "These studies indicate that EGb 761 may offer therapeutic benefit for the treatment of postinjury-associated thermal hyperalgesia and acute inflammation." Study Clarifies Ginkgo's Pain-Reducing EffectsThe researchers used a standard technique to induce pain and inflammation in the paws of rats. They then compared the effects of treatment with EGb 761, a standardized gingko formulation; and diclofenac—a nonsteroidal anti-inflammatory drug (NSAID) commonly used to treat arthritis and other painful conditions. These treatments were given in two different ways: local injection into the paw and central (intrathecal) injection into the spinal canal.

At both injection sites, EGb 761 had significant pain-reducing effects. In reducing thermal hyperalgesia, it was just as effective as diclofenac. The ginkgo extract effectively reduced swelling in the paw swelling, even when injected into the spinal canal.

EGb 761 had no effect on abnormal responses to mechanical stimuli, such as a pinprick (mechanical hyperalgesia). Diclofenac did reduce mechanical hyperalgesia.

In previous animal studies, oral treatment with EGb 761 has shown significant analgesic (pain-reducing) and anti-inflammatory effects. The new study was designed to clarify how these effects occur by comparing the effects of local (paw) and central (spinal canal) injection of EGb 761.

The results show that both local and central administration of ginkgo extract reduce inflammation and thermal hyperalgesia, with effects similar to those of a standard NSAID. The findings lend new insights into the specific pain pathways affected by ginkgo.

The study also adds to the evidence suggesting that gingko extracts could play a useful role in treating some types of inflammatory pain. More study is needed to further clarify how EGb 761 works, and to demonstrate the full range of its treatment and adverse effects.

Read the full articles in Anesthesia & Analgesia About the IARSThe International Anesthesia Research Society is a nonpolitical, not-for-profit medical society founded in 1922 to advance and support scientific research and education related to anesthesia, and to improve patient care through basic research. The IARS contributes nearly $1 million annually to fund anesthesia research; sponsors an annual forum for anesthesiology leaders to share information and ideas; maintains a worldwide membership of more 15,000 physicians, physician residents, and others with doctoral degrees, as well as health professionals in anesthesia-related practice; sponsors the SmartTots initiative in conjunction with the FDA; and publishes the journal Anesthesia & Analgesia. Additional information about the society and the journal may be found at the IARS website.

About Anesthesia & AnalgesiaAnesthesia & Analgesia was founded in 1922 and was issued bi-monthly until 1980, when it became a monthly publication. A&A is the leading journal for anesthesia clinicians and researchers and includes more than 500 articles annually in all areas related to anesthesia and analgesia, such as cardiovascular anesthesiology, patient safety, anesthetic pharmacology, and pain management. The journal is published on behalf of the IARS by Lippincott Williams & Wilkins (LWW), a division of Wolters Kluwer Health.