The British Heart Foundation is to run a campaign alerting young people to the hazards of cannabis smoking following wide-spread publicity about the drug last week.
The move comes as the Government prepares to take the controversial step of a softer line on the issue next year.
The foundation scored a publicity hit last week with a study which found that smoking three cannabis joints a day causes the same damage to the lining of the airways as 20 cigarettes.
That £10,000 study was sponsored by the Department of Health, which has now commissioned the heart foundation to press on with an education campaign warning 9 to 16 year olds of the dangers.
Despite also carrying a £10,000 budget, the foundation claims it wants a "high impact" campaign and is looking at various tactics such as SMS text messages and email.
It also plans to direct young people to its web site by running a quiz which will be publicised through the media.