A bad batch of what had been sold as ecstasy hospitalised 13 people in Christchurch. (Photo/ Getty)

It’s believed an early warning system to share information about dangerous drugs could have saved 13 people from hospital treatment in Christchurch.

They fell ill after taking a substance which had been falsely sold as ecstasy.

Drug testing outfit Know Your Stuff says if ambulance staff, emergency departments and coroners could share information about bad drug batches, incidents like this wouldn’t happen.

Victoria University senior criminology lecturer Fiona Hutton wants to see testing groups welcomed to all events where drugs might be present, to ensure people are aware of what they’re taking.

Fiona Hutton says a murky legal status means some events can’t advertise onsite testing.

“It puts people who know they’re stuff in an awkward, difficult situation which is a shame because what they’re doing is helping people and they’re reducing the harms from drugs.”

Ms Hutton says it makes sense for people to know what they’re taking.

“In the case of synthetic cannabis, we saw that it just didn’t happen which was very sad and had tragic consequences.”