A 1-year-old Staten Island girl was fighting for life in the hospital Monday after possibly overdosing on methadone, a narcotic used to help heroin and other opioid addicts combat withdrawal symptoms, authorities say.

Police responded to a 911 call near Grantwood and Roosevelt avenues around 8 p.m. Sunday and found the little girl unconscious. They administered Narcan, the emergency treatment for a known or suspected opioid overdose.

The baby was listed in critical but stable condition at the hospital Monday, police said. The investigation is ongoing.