“It’s worrying that children as young as seven are used as drug couriers,” Boonruang Triruangworawat, director of the National Narcotics Control Management Centre, said yesterday, which was the International Day against Drug Abuse and Illicit Trafficking.

Five 11-year-olds have been sent to drug-rehabilitation programmes this year, he said.

The government plans to rehabilitate about 220,000 drug users this fiscal year, said Boonruang, who is also director-general of the Health Service Support Department.

This year, 84,326 people have already undergone rehab, with teenagers aged from 15-19 years being the largest group.

Based on last year’s figures, methamphetamine accounts for 59 per cent of the country’s illicit drug consumption while marijuana is involved in 21 per cent of cases.

Drug cocktails or combinations of many drugs have also become more popular in recent years, accounting for 4 per cent in 2015, up from 0.05 per cent in 2011.

“It’s harder to rehabilitate those who use a variety of drugs,” he said.

About half of drug abusers start the habit after being persuaded by friends, while 41 per cent simply want to try it themselves.

“Families should help in efforts to make them give up drugs,” he said

“You can call for advice by dialling 1165.”

250m users worldwide

Globally, drugs have also become a serious threat.

According to the latest World Drug Report, 5 per cent of adults, or nearly 250 million people aged 15-64, used at least one drug in 2014.

Global seizures of synthetic drugs have risen more than sevenfold since 1998.

This surge has been largely driven by East and Southeast Asia, which have some of the largest and most rapidly growing methamphetamine markets in the world.

However, it appears that drug treatment centres in the region still lack the capacity to cope with the increasing number of methamphetamine users.

The number of people undergoing treatment for synthetic drugs has been increasing in Asia, particularly in Southeast Asia, while half of those who are treated in the region have abused opioids.