As China, India and other countries move to clamp down on these drugs, some argue that restricting access further could create different dangers.
Mykyta Lapin, an epidemiologist and head of the Ukrainian harm-reduction organisation Mind Games, says banning substances does not necessarily stop people taking them.
“Banning certain substances simply leads to people turning to the black market and buying drugs of dubious quality,” he says, risking overdoses.
Knowles says illicit pregabalin carries an extra risk because users may not know exactly what they are taking.
“If you buy an alcoholic drink from a shop [in the UK] and it says the amount of units it contains and its percentage, then that’s what it is.” He said the same certainty does not always apply to pregabalin bought online. “That’s an added risk that doesn’t come with a bottle of spirit.”
Matt, despite taking the drugs primarily as a social lubricant, remains convinced that he is also making the healthier choice.
“When I look at the improvement in my quality of life compared with what I see as a very minimal impact on my health, it’s such a clear trade-off,” he says.
“For me, it’s an exchange that’s worth it.”
Matt’s illegal habit remains heavily discouraged by most doctors. But still, with millions of young adults looking for a seemingly easy cure for anxiety, the numbers of people using these alcohol alternatives is likely to rise.
If you have been affected by addiction, help and support is available at Action Line. If you live in Northern Ireland, you can also call the 24-hour helpline Lifeline, on 0808 808 8000.
Top image credit: Getty Images.