Ketamine 'acts like magic' to lift depression, study says

Ketamine, the anaesthetic also used as nightclub drug known as Special K, acts like "magic" to relieve depression, according to researchers.

The drug quickly induces the regeneration of synaptic connections in the brain, a US study published in the journal Science has shown. Depressed patients who have resisted other treatments improve within hours, the study indicated.

The drug is not a practical therapy because it has to be administered intravenously, and can cause short-term psychotic symptoms, but the study could act as a guide to new treatments.