In Australia, so-called "synthetic substances" have been linked to several deaths in 2013, including that of a Sydney school boy who took an unknown substance believing it to be the psychosis-inducing illegal drug LSD.
The 17-year-old fell to his death from a third-floor balcony at his home, police say, and his family witnessed him acting "out of character" before the incident.
While the exact substance the boy took remains unknown, NSW Police believe his death could be the result of synthetic hallucinogenic substances 25B-NBOMe and 25I-NBOMe.
The most recent incident follows the death of another teen who died after being hit by a car on the Central Coast earlier this year after taking an NBOMe series substance.
Police are concerned the hallucinogen can lead to "reckless, risky behaviour" which in some cases can cause death.
Other associated side effects may include anxiety, panic attacks, acute paranoia and fear as well as high body temperatures.
NEW DRUGS THAT MIMIC OLDER ONES
Dr Monica Barratt from the National Drug Research Institute says the phrase 'synthetic drugs' is an anomaly, because traditional drugs are also often synthesised.
The term is often used to describe substances that mimic the effects of banned drugs, but in many cases may be new or relatively unknown.
Most synthetic drugs fall into two categories. Cannabinoids refer to cannabis-like synthetic drugs, while cathinones are similar to amphetamines or cocaine.
Organised crime is often at the heart of synthetic drug creation, with EUROPOL Director Rob Wainwright calling it a market with "low risks and high profits" for those inclined to create drugs that are technically legal in many countries.
The NBOMe series of substances have only really become known to authorities in the last year, says Dr Barratt.
"It's really hard to know how widely available they are because they are so new, our monitoring systems that we use, they haven't really caught up yet."
More than 70 new psychoactive drugs were officially recorded in Europe in 2012, continuing an upward trend on previous years.
In 2011, 49 new drugs were identified in the region, with 41 found in 2010 and just 24 in 2009.
"We don't have the same kind of monitoring system as they do in the EU," Dr Barratt says, "but given the globilisation of the market, it's likely that the same drugs they find will be present here, too."
Because new drugs often haven't been subject to the rigorous testing regimes of more well-known substances, the lack of information about what is in it, and how individuals might react is a big danger, says Dr Barratt.
"In any case, be it new synthetic or the standard list of prohibited drugs, the lack of purity, a lack of knowledge about content and what you can expect from the product is going to make it more dangerous," she says.