Ask Dr Gary: Legal but too often also lethal

Dr Gary says synthetic cannabis is an interesting topic.

We are preparing a submission to our local council which is looking to license shops selling legal highs. What is the impact on the respiratory or mental health of patients using recreational drugs such as these, and what long-term damage is done to babies in the womb exposed to this first-hand through the mother or secondhand passive smoking?

Synthetic cannabinoids are a fascinating topic. Thanks for your question. First, let's describe legal highs. To make them, you spray dried plant leaves (almost any kind) with synthetic chemicals. You sell them to kids and adults, who smoke them hoping to get high. And they do.

Unfortunately, a small percentage of users become anxious, paranoid, or aggressive. The chemicals make some users vomit, suffer fast heartbeats or delusions. Rarely, some become psychotic or have seizures. A sad few hurt or kill themselves - or others. Meanwhile, the people who make and distribute these chemicals do an amazingly profitable business.

The chemicals are mostly made in China or, rarely, in clandestine labs domestically, and they're structurally related to marijuana's active ingredient.

However, there are thousands of unique variations of these chemicals, and they're too new to really know what effects they have on health.

Medical literature shows various synthetic cannabinoids reduce inflammation, decrease pain, slow the growth of cancers, cause strokes and accelerate the development of schizophrenia.

People with psychiatric disease or pregnant women should avoid synthetic marijuana. The rest of us should too. Is it as devastating to society as alcohol abuse? No. Alcohol kills and maims more than synthetic cannabis. So far. But it's early days, and greedy manufacturers and users will keep trying to smoke newly invented chemicals in the eternal search for a high. Caveat emptor. Let the buyer beware.