A group of researchers from the University of Glasgow in the UK have confirmed the ability of Sativex, a medicine derived from marijuana, to relieve severe chronic pain.

The study, published online Jan. 13 2014 in the European Journal of Pain, involved over 300 patients suffering from a type of nerve pain called peripheral neuropathic pain.

Neuropathic pain is "one of the most difficult types of pain to treat," the authors say. Half of all patients fail to gain adequate relief through standard therapies.

The 15-week study was conducted at 39 different treatment centers, most of them in the UK. By the end, 28% of patients that received Sativex showed clinically-significant pain relief verses 16% that received placebo.

Patients were allowed to adjust dosing themselves, and only minor symptoms such as dizziness and nausea were reported.

Besides pain relief, the researchers observed improvements in sleep symptoms as well, which they say is consistent with prior studies involving smoked cannabis and a synthetic THC pill called Marinol (or dronabinol).

Other studies have also explained how marijuana works to ease pain. By binding to receptors at both the brain and spinal level, compounds in the plant seem to interfere with how the nervous system transmits pain.

The drug used in the latest study, Sativex, is a whole plant extract containing equal concentrations of marijuana's two main ingredients, THC and CBD, along with minor levels of various terpenes and other cannabinoids found in the plant.

The drug is made by British drug company GW Pharmaceuticals and is administered as an oral spray.

The latest findings should help GW Pharmaceuticals with obtaining regulatory approval of Sativex for patients with neuropathic pain. So far, the drug has been approved in 24 countries for treating multiple sclerosis.

The study received funding from GW Pharmaceuticals

Source: LeafScience