From tricking doctors to dealing with pushers in back alleys, people have tried various ways to get their codeine fix.
Psychiatrist Munidasa Winslow, an addictions specialist, said he sees about two cases relating to codeine addiction every month at his clinic in Novena Medical Centre.
In one case, a woman was guzzling 11 bottles of codeine syrup every day.
"When I asked why, she said, 'If you buy 10, you get one free,'" recalled Associate Professor Winslow.
Some people suffering from trauma or post-traumatic stress disorder symptoms also down the cough mixture to "blank out", he said, adding that one patient was so hooked on the mixture that he stockpiled about 80 to 100 bottles in his cupboard.
"Most (patients) have some experience with illicit drugs and are introduced to codeine through friends or peers," he said.
"Rarely do people discover codeine via doctors."
Some heroin addicts also reportedly turn to codeine as a cheap substitute.
A 90ml bottle may cost up to $10 at a clinic. In the black market, a similar bottle can cost about $35, though prices may vary.
When taken in high doses, codeine can trigger breathing and circulatory problems, and even death.
Due to its addictive properties, people have resorted to "doctor-hopping" to get their hands on it.
Dr Winston Ho, medical director of Parkway Shenton with a network of 56 clinics here, said its doctors are reminded to be alert.
"We are cautious with patients who insist on having only codeine-type cough syrups, and who appear clinically well when they come for a repeat visit."
There were cases of patients with suspected codeine issues last year, but "not many", said Dr Ho.
Doctors in the network are kept apprised of potential addicts, who may try to obtain cough syrup from other clinics in the group.
They are also barred from giving out repeat prescriptions of the medication to the same person without reassessing his health condition.
This article was first published on Jan 02, 2017.
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