Ketamine Treatments

Ketamine has been around for over 50 years. It was first synthesised by a professor of chemistry in Detroit in the USA in 1962 and, following research on its effect, it was first licensed for use as an anaesthetic in the USA in 1970.

Its effectiveness as an antidepressant was first recognised at the turn of the century and, although this important effect was forgotten about for a while, subsequent studies have confirmed that it is an effective antidepressant, with the benefits being evident within hours for some patients.

Ketamine works differently to most antidepressants. Whilst common antidepressant tablets work by increasing the amounts of a group of chemicals called monoamines, including serotonin and noradrenaline, ketamine increases the amount of another chemical called glutamate, through a complex chain reaction, and increases the connections between nerve cells in the brain. Therefore, it can be used alongside conventional antidepressants if required.

A common side effect experienced by people treated with ketamine is a feeling of dissociation: being somewhat out of body. One patient eloquently described it as feeling like a drop of water falling into the ocean. The intensity of this experience can vary from strange to frightening (at the extreme end), but there is some evidence that presence of dissociation is an important sign that a patient is receiving enough ketamine to possibly bring about an improvement in their depression. Other side effects, such as bladder problems, are common when ketamine is taken in large doses as a drug of abuse, but much less so when it is taken as a prescribed treatment for depression.

At present, ketamine is not licensed for depression, but, because of the evidence supporting its usefulness in treating depression, it can be prescribed ‘off label’ for depression. It is given as an intravenous infusion slowly (over 40 minutes) once or twice a week for an initial course of 6-8 infusions. There then follows a period of monitoring to assess whether any improvement is sustained or whether further treatments are required to keep someone who has benefitted from the treatment well. Patients can then carry on treatments every 2-4 weeks whilst being monitored on an ongoing basis.

When being treated with ketamine, because the effects are so rapid, close monitoring is required in between infusions. Patients are usually asked to record their mood daily using a simple scale, side effects are monitored after each infusion and more detailed questionnaires are completed at various points during the course of treatment. This ensures that any problems are picked up early and the treatment can be adjusted to suit each individual patient.