This week Alan Johnson, the Home Secretary, announced that three “legal highs” would be banned by the end of the year. Many people have not heard of the trio — GBL, BZP and “Spice” — yet they form part of an emerging crop of clubbing drugs. What — and how dangerous — are they?

GBL and GHB:

Street names liquid Ecstasy, herbal Ecstasy, coma in a bottle

Gamma-butyrolactone (GBL) is a clear, faintly odorous, oily liquid found in stain removers and paint strippers. Drug dealers sell it in small bottles or as capsules. Although GBL does not have “active” properties, it turns into the banned party drug GHB (gamma-hydroxybutyrate) when it enters the body. GBL has gained popularity as a legal substitute for GHB and has the same effects: it reduces inhibitions and creates feelings of euphoria.

Street value A 30ml plastic container costs about £15.

Legal status GHB is a Class C drug, meaning that anyone caught in possession faces up to two years in prison. GBL is marketed as a “legal high”, but may be reclassified as a Class C drug by the end of the year.

Risks Both GHB and GBL can be lethal, particularly when taken with alcohol. Other side-effects include coma, nausea, seizures and drowsiness.

BZP

Street names: herbal Ecstasy, legal E, Pep, A2, nemesis, exodus, frenzy, charge

BZP (benzylpiperazine) is a stimulant that comes in tablet form in many colours, usually stamped with friendly logos such as butterflies, smiley faces or hearts. It can also be bought as an off-white powder. The side-effects are similar to those of amphetamine: it causes dilated pupils, a dry mouth and a loss of appetite.

Street value From £3 a pill.

Legal status BZP is expected to be classified as a Class C drug by the end of the year. BZP is synthetic and is not a “herbal high”.

Risks Anxiety, nausea, vomiting, fits and collapse, particularly when mixed with Ecstasy, alcohol or amphetamines. It may also aggravate existing heart problems, leading to angina and heart attacks.

SYNTHETIC CANNABINOIDS

Street name: Spice

Synthetic cannabinoids are typically sprayed on herbal smoking mixtures that contain dried flowers and essential oils, which are often sold as “aromatic potpourri”. Synthetic cannabinoids mimic the affects of THC, one of the active chemical ingredients in cannabis, when smoked and have similar effects: users become relaxed and giggly or nauseous and introspective.

Street value £20 for a 3g pouch.

Legal status Currently legal, it is expected to be Class B by the end of the year — the same as cannabis and amphetamines.

Risks The same side-effects as the superstrength cannabis strain “skunk”: paranoia, memory loss and panic attacks.

NITROUS OXIDE

Street names laughing gas, hippy crack, Nos, N20

This clear gas, used in childbirth, has become popular on the festival and dance circuits. It is sold in canisters, then is released into a balloon and inhaled. Users report short-lived feelings of euphoria, giddiness and distorted hearing.

Street value From £2 a balloon.

Legal status Although it is legal to possess and inhale nitrous oxide, it is illegal to sell it for recreational purposes. Suppliers face a prison sentence of up to two years.

Risks Prolonged exposure can be fatal.Common side-effects include nausea, headaches and confusion.

2C-B and 2-CT-7

Street name T-7, 7-up, tripstacy They are sold as small tablets or as a white powder. Their hallucinogenic and euphoric qualities have led users to describe them as a kind of LSD-Ecstasy hybrid. Users have heightened sensitivity to colours, sounds and smells, and may also experience increased sexual arousal.

Street value Prices vary from £2-£5 a pill for 2C-B and £3 a pill for 2-CT-7.

Legal status Both drugs are Class A: illegal to possess, supply or sell. Possession can result in up to seven years in prison and supply up to a life sentence.

Risks Panic attacks and depression have been reported, although it is not known if either drug has any long-term effects.

KETAMINE

Street name Special K, horse, K

Liquid ketamine is legally used as an anaesthetic and as a tranquilliser for horses. Its illegal variant is a grainy white powder that is increasingly popular on the party scene. It numbs physical sensations and can also cause powerful hallucinations. Users report feelings of detachment; some claim to have had “out of body” experiences.

Street value 1g of powder costs from £15.

Legal status Ketamine is a Class C drug. Anyone caught in possession faces up to two years in prison.

Risks Ketamine can exacerbate existing mental health issues, causing panic attacks and depression. There have been reports of users failing to notice when they have seriously injured themselves because of the drug’s anaesthetic qualities. High blood pressure can occur when ketamine is mixed with Ecstasy or amphetamines. More than 20 deaths associated with ketamine abuse have been recorded in 15 years.

If you are concerned that someone you know is using drugs or if you want further information, visit www.talktofrank.com or call 0800 776600

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