KITCHENER -- Waterloo regional police say they responded to six overdose calls on Sunday.

In a tweet on Monday afternoon, officials said they're "reminding the public that street drugs are unpredictable."

"If you suspect that someone is overdosing, call 911 and administer Naloxone," the tweet said in part.

The Region of Waterloo's overdose monitoring report says emergency services have responded to 380 overdose-related calls so far this year.