Vancouver police say a young woman has died after taking ecstasy at a house party Saturday night, marking the fourth death linked to the drug in the last two months in the Lower Mainland.

BC Ambulance Service paramedics and firefighters were called to a home in the 5500-block of Larch Street at around 6 a.m. Sunday to treat a woman in medical distress.

Despite their efforts, the 22-year-old died in hospital. Her name has not been released at her family's request.

Const. Lindsey Houghton issued a warning about the "inherent risk and potential peril" of ingesting the drug, cautioning that there is no quality control in illegal drug manufacturing.

"This isn't made in a sterile pharmaceutical lab. This is made in garage, or bathtub or on someone's stove."

Investigators say the latest victim appears to have taken the party drug recreationally with several friends who did not suffer similar reactions, despite taking the same dosage.

"They took the exact same amount: one pill," Houghton said.

The incident follows similar tragedies that claimed the lives of 20-year-old Tyler Miller on November 27, 17-year-old Cheryl McCormack on Dec. 20 and an unnamed Burnaby resident who ingested ecstasy on New Year's Eve.

Abbotsford police say that McCormack appears to have been taking the party drug for weight loss purposes, while Miller used it recreationally with friends.

A 24-year-old Abbotsford resident was also rushed to hospital in critical condition on New Year's Eve after taknig ecstasy with friends, who say she may have taken more of the drug than they had.

Const. Ian MacDonald said he was last updated on the young woman's condition on Thursday, when she remained "fighting for life" and had yet to regain consciousness.

Several public warnings about the drug have been issued in recent weeks, but Houghton said people continue to put themselves at risk. To mitigate the chances of further tragedy, police are now urging users to pay attention to warning signs.

"If there is even the slightest hint of discomfort in your body or you react, phone 911 immediately. Don't wait, don't lie down and hope you'll get better," Houghton said. "Delaying could cost your life."