Aura medical director Associate Professor Graham Barrett said 30 patients had completed a course of injections, with three-quarters achieving a full recovery from depression, while another 35 were currently undergoing treatment. Each ketamine injection costs $150 and a typical treatment involves about 18 injections. Dr Barrett said ketamine was well established as a treatment for depression internationally and had a high rate of success but Australians were suffering while they waited for it to receive regulatory approval. "I think unless you have had depression or unless you know someone who has had depression you can't understand how severe that suffering can be," Dr Barrett said. Aura has links to the controversial chain of impotence clinics run under the name Advanced Medical Institute. The two companies share the same building in Sydney and the listed director and single shareholder of Aura, Michael Tattersall, is operations manager at Australian Custom Pharmaceuticals, which has prepared medications for and with AMI. Mr Tattersall did not return calls and an AMI operator hung up on the Herald when asked about the connection between the companies.

Black Dog Institute psychiatrist Professor Colleen Loo, who has conducted the only Australian trial of ketamine as a treatment for depression, said the results were promising but it was too early to introduce it into general clinics. "What we're finding is that a single treatment of ketamine usually given by injection form can cause an amazingly fast improvement in depression but for the majority of people it doesn't last more than a few days," Professor Loo said. Professor Loo said there ketamine was not an approved depression treatment anywhere in the world and there needed to be more research into dosage levels, side effects and how to make positive effects last longer. Sydney University Brain and Mind Research Institute executive director Professor Ian Hickie said the "off label" use of ketamine reflected the demand for more immediate treatment for depression but there were known risks of using the drug. Experts say those potential risks include damaging bladder function, increasing depression, inducing psychotic experiences or addiction, and affecting blood pressure.

"Jumping straight out of those experimental situations just because the drug is available and into private clinics is an inappropriate development at this stage," Professor Hickie said. Electrician John Schofield, 57, said he was thankful to have received 21 ketamine injections at Aura's Melbourne clinic. While at first apprehensive that the drug was not approved as a treatment for depression, he said nothing else could alleviate his suffering. "I thought nothing seems to be doing it for me. The antidepressants weren't really doing it, they helped me a little bit but it didn't give me a cure," Mr Schofield said. "I'm happy with the treatment. I think it's done something for me."