The largest trial into the use of electro-convulsive therapy (ECT) in the UK in more than 30 years has been launched, which will also look into how the use of class C drug ketamine might reduce the side effects of ECT for those being treated for severe depression.

Both ECT and ketamine are known to have benefits as antidepressants and as rapid and effective treatments for treatment resistant depression (TRD). 

However, ECT can also be associated with confusion and impaired thinking ability and memory. Ketamine is used as an animal and human anaesthetic and sometimes for pain relief, but cannot be used on its own as a treatment for depression. Previous small studies have suggested that combining ketamine with ECT can protect against the detrimental effects of the latter on thought processes and hasten the speed of recovery from depression, but a large-scale trial of the combination is needed before it is used in clinical practice.

The researchers hope that ketamine will reduce the longer-term loss of past memories, including autobiographical memory – which may include childhood holidays, growing up and early life –which can be a distressing side effect for people undergoing ECT.

In addition, they want to know whether ketamine will increase the rate of improving depressive symptoms, which may mean fewer ECT treatments are needed. An optional part of the study will be to include brain imaging to understand better how ketamine might be working in the brain.

Project manager Jo Lowe of the University of Manchester is coordinating the research team, which is led by Professor Ian Anderson. The trial is sponsored by Manchester Mental Health and Social Care Trust, and the study involves an additional five NHS Trusts and three universities.

Improving ECT

“It’s a great opportunity to really study ECT and see how we can improve it,” said Professor Anderson. “ECT is the most effective treatment we have for severe and treatment-resistant depression – but it can cause cognitive and memory difficulties as a side-effect. This is one of the reasons why not everyone who could benefit from ECT receives it, or is even offered the opportunity of having it. We believe that by combining ketamine with ECT these side effects on thinking and memory will be reduced or even prevented completely. This may make ECT a more acceptable option in the future.”

Ketamine will be given alongside the anaesthetic received during ECT, and those taking part in the study will be randomised to either receive ketamine or a placebo injection. 

Recruitment has begun for the trial, which is looking for 160 participants, all of whom will need to have been referred for ECT by their consultant. If you would like to find out more about the study, please visit the website: