Johannesburg - There should be greater drug monitoring of people such as pilots, doctors and other health practitioners, according to a professor in psychiatry.
Professor Solomon Rataemane, head of psychiatry at the George Mukhari Hospital in Ga-Rankuwa, was speaking at a two-day conference on the complexities of dagga and drug use in the context of possibly legalising it for medicinal use in South Africa.
"You don't know how many of the doctors you consult are high on something whenever you come to see them," said Rataemane.
He said a pilot might think it is okay to use drugs because he is only flying in 10 days. "Seven days later they are still under some influence."
Dagga use should also be considered as a factor in road accidents, said Rataemane, as a debate raged over why 249 people died in road accidents over the Easter weekend.
He took delegates through how dagga worked and how people consumed it - smoking, brewed, cooked.
Rataemane noted that there was research showing that dagga could be used to stop nausea, cut down on seizures, muscle stiffness, migraine and cancer.
But this was using very small regulated amounts of Tetrahydrocannabinol (THC), which is active chemical in cannabis, provided by doctors certified to prescribe it.
The Federal Drug Agency in the US had already approved two drugs that included ingredients found in dagga.
People use tiny regulated concentrations of Cannabidiol, a cannabis extract for health for relief and some research has suggested that it may be helpful but "it doesn't cause you to get high", he said.
"I think scientists have to continue to help us isolate cannabinoids because some are toxic."
A history of drug use
Rataemane said between 40 to 60 percent of the young patients admitted to the psychiatric ward had a history of dagga and drug use included in their admission assessments.
They suffered from mood changes, paranoia, delusions, but after about three days, when the drugs started wearing off, were feeling much better and wanted to go home.
Studies have found that long term dagga smoking is associated with a drop in IQ, impairments in memory and in some cases schizophrenia, he told delegates. It was also associated with lung and throat cancer.
Inkatha Freedom Party MP Mario Ambrosini tabled the medical innovation bill as he battled terminal lung cancer to start a debate over cannabis for medicinal purposes. He died in 2014, but the discussions on Thursday formed part of information gathering and debate on the controversial subject.
"We don't have enough studies in this country but I think we do have a direction in terms of the bill," Rataemane.
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