The class B party drug ketamine could be used as a last-resort treatment for sufferers of severe depression, Oxford University scientists say.

For six years, Oxford scientists have used approximately 1000 infusions of the horse tranquilliser to treat more than 100 people with treatment-resistant depression.

Shoryu HT20 Side Banner

They said that patients who received carefully administered intravenous doses of the drug, followed by oral top-ups, reported positive effects in 42 per cent of cases. The drug was slowly injected over 40 minutes once or twice a week.

“I have seen ketamine work where nothing has helped before,” said Dr Rupert McShane, a consultant psychiatrist at Oxford Health NHS Foundation Trust, who led the programme.

“But ketamine is a drug not a miracle, and maintaining the benefit is a challenge. So far, the only way we have found to maintain the benefit is repeated dosing.

“We think that patients’ treatment should be in specialist centres and formally tracked in national or international registries.

“This will help us to pick up any safety or abuse problems with longer term use, and narrow down what dose, frequency, route and duration of treatment works best.”

Among a range of recommendations listed in the paper, published in The Lancet Psychiatry, the authors say that there is a need for clear guidelines and registries to track results about how patients with depression respond to ketamine.

They suggested further investigation into working out the safety of repeated ketamine treatment, and the potential for misuse.

Ketamine — also known as ‘K’ and ‘Special K’ — is known for giving its users dreamlike, “floaty” feelings, sometimes referred to as “entering the ‘K-hole'”.

It is banned for recreational use in the UK, but is currently a licensed drug, which means it can be prescribed by doctors. In the last year, there has been a boom of private ketamine clinics in the US.

The paper concluded: “We hope that the recommendations proposed here go some way to enabling innovative use of ketamine for treatment-resistant depression to continue, with appropriate care, precaution, and foresight.”

Professor Allan Young, of the Royal College of Psychiatrists, said ketamine may cause some mood improvement for sufferers, but “there are still significant gaps in our knowledge about dosage levels, treatment protocols and the effectiveness and safety of long term use.”

“Before ketamine can be recommended for use in clinical practice, extensive research is required to understand how to optimally use ketamine for treating depression.

“The Royal College of Psychiatrists has concerns for patient safety; and hence recommends mental health practitioners to proceed with caution when treating patients with ketamine.”