What is ketamine?

Ketamine is an anaesthetic widely used across the world in hospitals. The dose of ketamine administered in this trial is substantially less than that used in hospitals, and repeat high doses of ketamine are commonly given to patients. In the low dose which will be used in this study, ketamine has been shown to lead to short term improvements in mood, lasting up to 7 days, in individuals with depression which has not responded to treatment.

People sometimes abuse ketamine because of the effects it can have at a high dose. However, the dose chosen for this study is well tolerated in humans. Patients may experience some changes in vision and hearing and other senses like touch while having the infusion of ketamine. Patients do sometimes report having hallucinations. Any changes experienced should resolve quickly.

The treatment administered in this trial does involve having a needle put into a vein on the back of the hand as the ketamine is infused over 40 minutes. There is therefore a chance of temporary bruising in this location.