Harry Shapiro: What you see in drugs may not be what you get

The emergence of so-called "legal highs" means another layer has been added to the existing market in psychoactive substances. While the Government might control various legal highs through legislation, in terms of public health and safety advice, these drugs are not more "reliable" or safe than more familiar drugs like cocaine or ecstasy.

Users might buy the same packet containing a substance that looks the same as one they bought previously from a website or headshop, but the drugs might be different – with different potency or effects. There is no more "quality control" in the legal highs market than if you were buying heroin or cocaine.

A lot of the substances known as legal highs have already been controlled. The Government has brought mephedrone (known as miaow miaow) and synthetic cannabinoids such as Spice under the Misuse of Drugs Act.

One issue is the speed at which new substances become available and how long they sit outside the legal framework. The Government, drug agencies and health professionals are sometimes playing catch up. From an enforcement point of view, this is a major challenge, particularly if the drugs are bought online.

Small scale home production of most of these substances is unlikely. There may be a move from traditional producer countries for illegal drugs, like Peru, Afghanistan and Colombia, into China and eastern Europe, which have many chemical factories and large pharmaceutical markets. We are starting to see new outlets for production.

It's partly a damage limitation exercise, but drugs often go in cycles, based on availability and price. In the 1980s, glue sniffing was more common and ecstasy was a major drug trend in the UK. It is hard to pin down why cycles change. Legal highs are a phenomenon of the last few years, while other drug scenes go back 10 to 20 years, or more.

It is difficult to predict what the impacts will be, but at the very least, we are adding a new and significant dimension to the world drugs situation.

The writer is director of communications for DrugScope