When 72-year-old Anna Stratakos asked a flight attendant for a barf bag, she never imagined it would lead to Air Transat forcing her off the flight, leaving her stranded at the Athens airport.

"You don't know what happened to me that day, what I've been through," said the grandmother, who cried while retelling her story — which included paying about $800 to rebook her flight.

After visiting family in Greece, Stratakos boarded an Air Transat plane alone on July 12 to fly home to Toronto. She says she felt a little light-headed following a long taxi ride to the airport, so she asked for a barf bag as a precaution.

Stratakos claims the flight crew incorrectly assumed she was sick and kicked her off the plane.

Anna Stratakos, right, visiting family in Greece. (Submitted by Goerge Stratakos)

In the past eight months, four passengers (including Stratakos) who boarded separate flights on three different airlines have complained to CBC News that they were removed from their flight for medical reasons they felt were unfounded.

According to federal aviation regulations, airlines must deny boarding to passengers who show signs they could pose a safety risk to themselves, other passengers or flight operations.

But some passengers who feel wronged question the methods airlines use to make their decision.

"I'm not vomiting, nothing," Stratakos said. "I said, 'No no, I'm not sick.'"

But the flight crew disagreed.

Air Transat said Stratakos indicated she was unwell and "exhibited symptoms of dizziness and nausea." In response, the flight's captain contacted Medlink, a medical service that provides airlines with passenger assessments by phone.

"Medlink assessed that Mrs. Stratakos was unable to safely complete the flight and advised us that it was best to disembark her," Air Transat spokesperson Debbie Cabana said in an email. She didn't provide further details of the diagnosis.

$1,500 travel bill

After Stratakos refused to leave, the flight crew called airport security to escort her off the plane.

Air Transat said when passengers are removed from a plane following Medlink's advice, they're referred to the airline's 24-hour hotline to make new travel plans.

Stratakos says she received no medical followup and was directed to the Air Transat counter at the Athens airport, where an employee informed her she'd have to purchase a ticket for another flight.

Stratakos paid about $800 to book the next Air Transat flight home through a travel agency at the airport. She says she also paid more than $700 total on taxis to and from the city of Kalamata — almost 270 kilometres from the Athens airport — to stay with family until her flight departed four days later.

"I pay so much money for nothing," said the widow, who lives on a fixed income.

Air Transat says Anna Stratakos indicated she was unwell and 'exhibited symptoms of dizziness and nausea.' (CBC)

On Sept. 6, Stratakos's son, George, sent a detailed email to Air Transat, complaining about how his mother was treated and asking the airline to cover her flight home and taxi fares.

"I can't imagine just being thrown off a plane," said George Stratakos, who picked up his mother from the airport in Toronto.

"When we got home, she burst into tears. I mean, she was literally crying about the situation. She was embarrassed."

Doctor on call?

Shortly after CBC News contacted Air Transat last week, George Stratakos received an email response from the airline that included an apology for not replying sooner.

Air Transat said "given the inconveniences suffered by Mrs. Stratakos and any ensuing miscommunication that could have occurred," it will refund her return flight and taxi fares, if she provides receipts.

George Stratakos says his mother didn't collect cab receipts. He also questions the methods the airline used to diagnose her.

"I believe that Air Transat's employees overreacted, and made overreaching decisions," he wrote back to the airline.

That's the same conclusion WestJet passenger Stephen Bennett reached when the airline kicked him off a flight in October after he took a sleeping pill and fell into a deep slumber, raising concerns among crew members.

Passenger rights advocate Gabor Lukacs says airlines have a responsibility to call a doctor when diagnosing a sick passenger before takeoff. (CBC)

Air passenger rights advocate Gabor Lukacs argues that if an airline thinks a passenger is sick, it is obligated to call an independent physician who can assess the passenger in person.

"The airline should call a doctor for the passenger's own well-being," said Lukacs, founder of Air Passenger Rights, a Canadian non-profit group.

"[The doctor] can examine the passenger and can confirm whether the passenger is or isn't fit to travel."

He says if the flight must take off before the doctor arrives, the passenger can stay behind to wait for the physician. In that case, if the passenger does get a clean bill of health, they should get the same compensation airlines pay when passengers are involuntarily bumped from flights, Lukacs says.

"If they are wrong, then they will be on the hook."

Transport Canada says the decision to remove a passenger for medical reasons "is at the discretion of the flight crew."

Edmonton aviation consultant Ken Beleshko says airlines make these decisions cautiously. Their only obligation, he says, is to determine if a passenger poses a risk and should be removed from a flight.

"It's up to the passenger, really, to satisfy the airline that they're medically fit."