The pounds 236,000 campaign is aimed at young clubbers and tells people about the good as well as the potentially harmful effects of different drugs.
The campaign is a new approach to drug users, using "club" language and artistic designs and has moved away from the negative images of previous information bulletins.
Organisers of the London Dance Safety Campaign want to reduce the risks involved in taking illegal drugs. However it is expected to upset and anger some anti-drug campaigners who will argue that it encourages law breaking and abuse, particularly of substances such as ecstasy.
The campaign, which is launched tomorrow, is concentrating on clubs and drug users in London. A series of six posters are going to be placed on the capital's tubes and buses. There will also be 150,000 special drug booklets, and training for staff at nightclubs.
The organisers are targeting six drugs that are commonly taken in clubs - ecstasy, LSD, amphetamines, cocaine, poppers and cannabis.
The poster for ecstasy states that the drug is: "associated with heightened perceptions and euphoric sensations of empathy and warmth". It says that lots of water, not alcohol, should be taken with the drug in clubs.
It does, however, warn that "studies indicate that ecstasy affects both brain cells and the liver, but its long term effects are not known yet. Users may also suffer depression."
The campaign is being carried out by the London Drug Action Teams, who received pounds 142,000 of government funding. Mike Goodman, director of Release, the national drugs organisation which is involved in the campaign, said: "This is all about harm reduction and minimising risks. It does not have advice saying don't take drugs, although that is implicit. It is not preaching, it just states the risks.
"It recognises that there will always be a large number of people who take drugs and that many are ignorant of the risks.
"This is a new type of approach - we are moving away from the negative imagery, such as the old `Heroin Screws You Up' campaign."
John James, chief executive of Kensington, Chelsea and Westminster health authorities, who is a spokesman for the campaign, added: "In a perfect world no one would take drugs but we live in the real world. The purpose of this exercise is to give young people the facts in a non- emotive, non-judgmental way."
It follows the current Health Education Authority radio and magazine advertising campaign, in which drug users are urged to "know the score" about illegal substances, particularly ecstasy, speed and LSD.
The new advertisements, commissioned by the Department of Health, are aimed at encouraging users to think again and give teenagers who do not take drugs solid reasons to say `no'.
The campaign also promotes the National Drugs helpline number, 0800 776600.Reuse content