SINGAPORE - Former users said Ritalin can cause a "bad crash" after its effects wear off.
Side effects of indiscriminate consumption can include nausea, vomiting, high blood pressure, abnormal liver function and hallucination. The Straits Times understands there are online forums dedicated to using Ritalin as an alternative to cocaine.
Dr Chan Herng Nieng of Singapore General Hospital acknowledged that while methylphenidate - which is in the same class as methamphetamine - is sold in the black market overseas, "thankfully I have not seen anyone coming to me asking for Ritalin straight out".
Addictions specialist Munidasa Winslow has not dealt with cases of Ritalin abuse, though he has "heard of a few".
"With Ritalin, there is less risk of addiction but the problem arises if such users turn to higher stimulants later," he said.
Some students are crying foul that their pill-popping peers have a leg-up in their work. One, aged 24, said: "It's like steroids and not fair to everyone else trying to work hard."
First-year law student Clement Lin, 21, does not think that unauthorised Ritalin consumption is cheating - even though he has neither taken the pill, nor plans to.
He said: "We must distinguish between the act of buying pills from friends, which is illegal, and the act of taking the drugs to boost memory, which is a bit more of a grey area."
Under the Medicines Act, the penalty for importing or selling medicines illegally is a fine of up to $5,000 and/or up to two years' jail.
The Health Sciences Authority said it has not prosecuted anyone on illegal import or sale charges involving Ritalin in the last five years.
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