Police warn about 'sparkle' – the new legal high

Just hours after the ban on mephedrone came into force, officers are on the alert for yet another party drug

Police have been put on alert for another dangerous "party drug", just hours after the ban on mephedrone came into force. Officers from around the country have flashed warnings about the rise of a legal high known as "sparkle" in recent months, as a series of deaths connected to mephedrone brought the synthetic stimulant to national attention.

Users report that sparkle, also dubbed "legal MDMA", provokes effects including euphoria and increased brain activity similar to the Class A drug ecstasy. The UK's biggest online "head shop", selling drug paraphernalia, herbal stimulants and plant cultivation equipment, reported it had sold out of sparkle, which sells for £40 a gram.

However, the content of the drug is shrouded in mystery – and even police and government experts admit they were unaware of the full details of its ingredients and effects.

Details of the gap in the authorities' understanding of the latest legal high emerged as internal documents reveal that a government drugs helpline was unable to warn callers of growing fears over mephedrone because it lacked information on it.

The Independent on Sunday has established that experts answering calls on the killer drug warned their bosses about the rising tide of concerns over legal highs almost 18 months ago – but later complained they did not have any information or advice to offer worried young people and parents.

The Home Office has now acted to make mephedrone a Class B substance. West Mercia Police arrested and charged a man in Bewdley, Worcestershire, with possessing the drug just hours after it was made illegal. The drug has been linked to a number of deaths, although there is no conclusive scientific proof yet that it has been solely responsible for any of them. The Advisory Council on the Misuse of Drugs (ACMD) recommended a ban. People possessing it now face up to five years in jail.

Law-enforcement attention has now switched to the potential dangers of more legal highs, notably sparkle, which is already being marketed as a legal alternative to mephedrone. "We have had emails about this one from operational cops all over the country for the last few months," said Mal Taylor of the Police Federation. "We have had all sorts of slang names given to these substances in different parts of the country. We are looking into sparkle, but we just cannot say yet what is involved or exactly how dangerous it is."

An adviser from the Frank drugs helpline last night admitted they had no official information on sparkle. "We are not fully aware of the full risks because there has been no research into them. There is a risk of death," she said.

Papers obtained by the IoS show as recently as eight months ago, with anxiety over mephedrone escalating, the Department of Health had still not equipped its front-line drugs advisers with information to ease public fears. Despite the former home secretary Jacqui Smith ordering a review into legal highs, Frank staff were not given information to allay callers' fears.

A document from April 2008 reported "an increase in calls about legal highs regarding risks and effects as callers often state 'they're legal so they must be OK'". However, later in the year, the helpline's experts reported that "parents [were] asking why Frank does not give information or advice on specific legal highs".