Frances Oldham Kelsey passed away on August 7 at the age of 101. This physician is credited with saving the world from a dangerous prescription drug with disastrous side effects. 

Thalidomide was briefly prescribed to pregnant women during the 1960s, in order to relieve feelings of nausea. But it soon became clear that the drug was responsible for serious birth defects, including missing limbs and organs, causing lack of vision and hearing. Some victims were born with arms and legs shaped like flippers. 

Kelsey's job at the U.S. Food and Drug Administration (FDA) had her overseeing the approval process of the drug. The Canadian doctor staunchly fought against approval, speaking time and again about the dangers of the medicine. 

William S. Merrell Company of Cincinnati, which manufactured the drug, refused to send Kelsey the information she requested about the drug. 

In England, Europe, Canada and the Middle East – where the drug was largely used – babies were being born with serious birth defects. Kelsey's opposition to FDA approval helped keep the drug from widespread use in the United States, potentially saving millions of people from severe birth defects. 

"Her exceptional judgment in evaluating a new drug for safety for human use has prevented a major tragedy of birth deformities in the United States," said President John F. Kennedy in a White House ceremony honoring the medical researcher. 

Kelsey's work helped to drive new laws in the United States, requiring drug manufacturers to prove the safety and efficacy of their products before marketing them to the public. 

Perhaps due to the fact that Kelsey spent much of her life in the United States – where she became a naturalized American in 1956 – she was not formally recognized for her work by the government of Canada. Shortly before she passed away, Ontario officially recognized her work, presenting her with the Order of Canada. 

"We knew that death was imminent, and I sat beside her bed, held her hand, told her why I was there and why it was so important that we have the opportunity to recognize her, and took the medal and had an opportunity to put it in her hands," said Elizabeth Dowdeswell, lieutenant governor of Ontario.

Before Kelsey's efforts, FDA approval of new drugs was often routine, and the manufacturer had millions of doses in warehouses, awaiting shipment to doctors and hospitals.