The mother of a 23-year-old man says a single dose of a deadly street drug killed her son.

Bev Robertson's son Adam died after injecting Fentanyl last April.

Robertson is sharing her story about the drug in the hopes that other parents will know what to watch for and be able to get help for their children before it's too late.

"It can kill you—there's no question about it," says Robertson.

Fentanyl is a powerful pain medication normally used for treating terminally ill cancer patients. The dosage is usually released over a three-day period through a patch.

The patch, however, is also being sold by some people for use as a street drug.

Dr. Lindy Lee says drug addicts will use Fentanyl in a number of ways. Some will cut the patch in pieces and chew on them, while others will inject it using vinegar or some form of citric acid.

Dr. Lee says the reason the Fentanyl can be so deadly when used as a street drug is because it's supposed to be released slowly.

"Instead these young people inject it over a matter of seconds and it's not unusual for them to stop breathing and require resuscitation by other friends, or even to die," says Dr. Lee.

A former drug dealer and addict who spoke to CTV News says he's seen first hand how dangerous Fentanyl can be when used as a street drug.

"I lost lots of friends," says the man, who did not want to be identified.

Before her son died, Bev Robertson says she found vinegar and spoons inside his bedroom, which she later realized he used to mix up Fentanyl as part of his addiction.

Robertson's son had tried to get help with his addiction but it came too late. A day and a half after Adam overdosed and died, a treatment clinic called his home to say he could come in.

Robertson told them it was too late for her son.

- with a report from CTV's Rachel Lagacé