Queensland Health has launched an investigation following a recent influx of patients to hospitals in the Metro South area, including Logan and Princess Alexandra facilities.

An internal safety notice, issued by Chief Health Officer Dr. Catherine McDougall, alerted staff to a concerning cluster of cases involving rat poison detection in patients.

Medical professionals have been advised to closely monitor individuals exhibiting unexplained bleeding symptoms, which may indicate exposure to the toxin.

The investigation suggests that the affected individuals may have consumed rat poison through contaminated food items at a fast-food restaurant in Logan.

Dr. McDougall informed 9News that efforts are underway to pinpoint the exact source of the contamination.

Rat poison reduces vitamin K in the body, which decreases a person’s ability to clot blood and can be very serious in some cases.

All five patients who turned up sick at hospitals are receiving treatment and are expected to be okay.