A woman in Florida says an airline told her to flush her hamster down an airport toilet because the emotional support rodent wasn't allowed to fly with her.

The Miami Herald reports Belen Aldecosea flew home from college to South Florida, having twice called Spirit Airlines to ensure she could bring Pebbles, her pet dwarf hamster with her on the flight.

But when Aldecosea arrived at Baltimore airport, Spirit refused to allow the animal onboard.

The 21-year-old told the paper she flushed Pebbles at an airline employee's suggestion, after running out of other options.

Panicked and needing to return home promptly to deal with a medical issue, Aldecosea was unable to rent a car and agonised for hours.