JOHN (not his real name) seems like any first-year university student - except that he sleeps just two hours a day.
In fact, he sleeps only 30 minutes at a go, after every 51/2 hours of waking time.
The 21-year-old has been taking wakefulness-boosting drugs for the past three years, which keep him alert even with hardly any sleep.
This allows him to juggle school work and run the two businesses he owns - a trade-related business and a sports venture - even late into the night.
John is among a sizeable number of tertiary students and young executives here who are turning to such drugs to lengthen their waking hours.
They include John's close circle of 15 university friends who are also student businessmen in their early 20s, and at least three more groups here, he said.
One of these consists of student entrepreneurs; another of tertiary students who want to ace their studies; and the third of finance professionals in their late 20s who want to improve their work performance.
And with the university exam period this month, other students have approached John to buy the drugs to cope with last-minute cramming.
John and a friend first found out about the drugs when they were researching online on ways to stretch their time to run businesses despite being occupied with army and university.
John gets his supply of drugs - made in countries like South Africa, France and the United States - from online pharmacies and his own suppliers. He sells each tablet for $1 to $5, close to the cost price.
The drugs include modafinil and methylphenidate, which are controlled drugs used to treat excessive sleepiness.
Methylphenidate, registered for use here with the Health Sciences Authority (HSA), can be prescribed only by a doctor.
Doctors can apply to HSA to import modafinil, which is not registered here, to treat patients when it is clinically justified, said an HSA spokesman.