Two numbers and a quotation sum up the dilemma facing parents concerned about drugs and their children but unsure of where to get help.

Buried in the report by the Roehampton Institute in London is the finding that 76.5 per cent of parents did not know what services existed in their area, but 56 per cent did know where to go to find drugs. Or in the words of one parent, asked the best place to go for advice and support: “I would go to Yellow Pages, I think. Look it up under D.”

The report is littered with quotes from parents illustrating their sense of frustration and helplessness. One says: “It’s very difficult to differentiate between the signs of someone taking drugs and the normal problems of teenagers. Drugs induce big mood swings - but so does just growing up.”

Three-quarters of parents said they wanted information on the signs of drug abuse; 69 per cent wanted access to booklets or leaflets.

What they do not appear to know is that pamphlets already proliferate. One published last year to government fanfare is the Health Education Authority’s most-ordered leaflet ever.

Dr Roy Evans, who led the Roehampton research, said schools had to be more pro-active. Simply sending leaflets home was not enough, especially when some parents who needed the most help often had poor literacy skills.

Some schools had failed to adopt a drugs policy at all, fearing that just having a policy would make parents think the school had a problem.

Government agencies have recognised that drug prevention needs to be more about education and less about scaremongering, reflecting an acceptance that a growing number of pupils are experimenting with illegal drugs.

But mixed messages continue at the highest level. Tony Blair, announcing his plans for a “drugs czar” to a teenage audience in March, told them to “Just say no”.

Researchers contacted a range of 36 secondary schools in Kent. Forms were sent to 27 to distribute to 100 Year 9 and 10 parents via their children. The response was around 50 per cent. Fifty parents were interviewed by telephone and focus groups of six parents each were run in four primary and three secondary schools.

Drugs education: a parents’ needs study is available price Pounds 7.95 from Pauline Lewis, CEDARR, Froebel Institute College, Roehampton Institute London, Roehampton Lane, London SW15 5PJ. Cheques payable to Faculty of Education.