Ketamine review ordered by Home Office

While medical ketamine comes as a clear liquid, street ketamine is usually a white crystalline powder

A review of Class C drug ketamine has been ordered by the Home Office.

It follows concerns about its increased use and the harm the drug can cause.

Home Secretary Theresa May has asked independent experts on the Advisory Council on the Misuse of Drugs (ACMD) to update their advice.

High doses can suppress heart function and lead to unconsciousness, with some regular ketamine users experiencing serious bladder damage.

The review will run alongside other aspects of the ACMD's annual work programme for 2012/13, which includes monitoring new psychoactive substances - so-called 'legal highs' - as well as reviews into khat and cocaine.

The government has grown concerned about the increased popularity of ketamine among young people.

Home Secretary Theresa May said: "Our annual work programme sets out the government's priorities for tackling drug issues over the coming year, and seeks expert advice from the ACMD to help develop our evidence-based drugs policy.

"As well as the council's important ongoing work, we are becoming increasingly concerned by new evidence and heightened public concern about the popularity and potential harms of ketamine, which is why I have asked the council to revisit its earlier advice on the drug."

Last week a review was launched to establish whether methoxetamine, a so-called legal high which is sold online as a safe alternative to ketamine, should be banned.

Memory deterioration

Best known by the street names K, Special K and Vitamin K, the drug is a synthetic "dissociative" anaesthetic used for medical and veterinary purposes.

Its chemical name is 2-(2-chlorophenyl)-2-(methylamino)- cyclohexanone.

First reports of ketamine's use as a recreational drug started after its release into the market in 1965.

It gained popularity in the UK nightclub scene in the early 1990s as people bought it in the mistaken belief that it was ecstasy.

Ketamine is dose-specific, so the amount taken determines the level of effect.

At low doses the user may feel euphoric, experience waves of energy, and possibly synaesthesia - sensations such as seeing sounds or hearing colours.

However, some evidence suggests that use of the drug has an effect on memory, which persists for longer than three days after use, and becomes worse for regular users of the drug.