The street drug called “whoonga” is a cocktail that includes the antiretroviral (ARV) medication prescribed to people with HIV.
Demand for the substance has prompted A wave of thefts of AIDS drugs across the country.
Users crush the ARVs and smoke them with a mixture of rat poison, detergent and marijuana to get high.
The powder is said to be so addictive that users are hooked within days.
“If I don’t smoke it, I get pains and I can’t sleep until I get some more,” 31-year-old Jomo said, his eyes red and glazed after a few deep drags on a ‘joint’.
HIV medication has become a target for thieves in South Africa
He and his fellow whoonga addicts, huddled in the grounds of a church in one of Durban’s side streets, smoke up to 30 “packets” of the drug every day at a cost of almost £100.
“I just rob people to get the money. I don’t have a job, this is all I do,” Jomo said, rolling another joint.
“I sell my body to get whoonga,” a young woman said with a shrug.
When those sharing the joint refused to share it with her, she produced a crack pipe from her handbag and smoked that instead.
In the back streets of Durban, Whoonga dealers tout the powder for 30 rands (about £3) per packet.
The highly-toxic drug has been blamed for the deaths of scores of addicts across South Africa during the past year.
We are not even convinced that whoonga contains ARVs. The dealers just say it does.
Caroline Nenguke, Treatment Action Campaign spokeswoman
In the township of Umlazi, near Durban, officials say dozens of AIDS patients are being robbed of their antiretroviral drugs every week.
Sithenjwa Nyawose, local ANC councillor, said: “The patients are being mugged for their drugs. They are violently attacked in the streets as they leave the clinics.”
In Johannesburg, a police officer was implicated this month in a cartel that has targeted health clinics to steal ARVs.
Doctors say the prescription medication does not contain anything that could deliver a “high”, even when smoked.
The country’s Treatment Action Campaign, an Aids lobbying group, has described the belief that the drugs have recreational value as a “myth”.
Group spokeswoman Caroline Nenguke said: “We are not even convinced that whoonga contains ARVs. The dealers just say it does.”
Either way, Ms Nenguke warns the whoonga craze is fueling a growing illegal trade in HIV medication that could damage the country’s efforts to make Aids treatment more widely available.