Pearson, who lives on the Gold Coast, said she broke down in tears when she realised she had to withdraw from what are likely to be her last Commonwealth Games.
"Of course, I did everything I possibly could," said the 31-year-old former Olympic champion. "I left no stone unturned to get out here and race for Australia in the 100m hurdles and the 4x100m relay.
"Everyone knows how much of a competitor I am and how much I love running for my country and my team-mates.
"I know I have a lot of fans who were wanting to watch me race. But for me, it is about my health and I want to go to the Tokyo Olympics in 2020."
Pearson has been plagued with problems to her achilles and her announcement was a blow to Australia's medal hopes.
Flora Duffy won the opening gold medal of the 2018 Games. The 30-year-old from Bermuda, who will also compete in mountain biking, won in 56 minutes and 50 seconds to end Bermuda's 20-year medal drought and become the islands' first female medallist. England's Jessica Learmonth was second and Joanna Brown from Canada took bronze just a month after breaking her shoulder.
Henri Schoeman from South Africa claimed gold ahead of Australia's Jacob Birtwhistle in the men's triathlon. England's Alistair and Jonny Brownlee, the Olympic gold and silver-medallists, finished 10th and seventh respectively.
In weightlifting, Malaysia's Muhammad Azroy Hazalwa set the a Commonwealth record with a total of 261kg to win the men's 56kg class.