Three deaths in Edmonton's inner city have prompted health officials to warn of a possibly toxic brew of drugs being sold on the street.

The victims arrived at the Royal Alexandra hospital this month with extremely low blood sugar. Another two people turned up with the same symptoms, but survived.

The common factor among all the patients is the use of illegal drugs, Marcia Johnson, Edmonton's deputy medical health officer, said Thursday.

She suspects a dealer is using diabetic medicines that lower blood sugar as a filler in street drugs.

"We are theorizing that it is related to illicit drug use, and possibly one of the agents or one of chemicals that might result in low blood sugar is being distributed or mixed in with the drugs on the street."

Police waiting for autopsy results

Police can't confirm that the three deaths were caused by drug use until autopsies are completed.

Police say mixing such drugs as crack and and ecstasy with other chemicals is a common trick used by drug dealers to maximize profits. The mixed substances are known on the street as "stepped on" drugs.

"It is cut and you can taste it and you know that it's been stepped on. They step on a lot of things to make more money," said Valerie Paddy, a homeless woman in Edmonton.

Sgt. Darcy Strang of the Edmonton police drug section said it's unlikely someone is intentionally hurting people.

"It's stepped on for the purpose of making more money and sort of bolstering the actual drug itself." he said. "But it's not necessarily stepped on to hurt somebody else. It's not to say that couldn't happen, however, it would be uncommon."