His career has focused on child health - he created New Zealand's first digital health programme, iMoko, which delivers healthcare to children across the country.
Late last year O'Sullivan told the Rotorua Daily Post he had strong links to Rotorua.
"I started my career in Rotorua, my family and children whakapapa to Rotorua and it helped form me to be the person I am today as a clinician."
O'Sullivan is also renowned for his work to improve health outcomes for whānau in the Far North.
In the past, the outspoken doctor has been vocal about the importance of immunisation — disrupting a screening of a controversial anti-vax film.
In a Facebook post in April, he admitted breaching Covid-19 alert level 4 lockdown rules and going kayaking.
"We've been living in a campervan doing our work for the Kaitāia community, but on the weekend I went for a kayak to a place not far from the place I'm staying," he said.
"I'm a dick and I f**ked up. F**k, what a silly bugger, eh? A silly bastard."
Dr Lance O'Sullivan at the launch of iMoko health screening project in 2018. Photo / File
Merepeka Raukawa-Tait, who is a Rotorua Lakes councillor, Lakes District Health Board member, Whānau Ora's North Island Commissioning chairwoman and the former chief executive of Women's Refuge, said todayshe was "sorry to hear Dr O'Sullivan has had a spot of bother".
"A few years ago I travelled with him throughout the United States. I know he is committed to improving the health and wellbeing of families, particularly those who struggle daily to make a better life for themselves.
"We do place high expectations on those who have a high public profile but an isolated case of stupidity should not detract from the years of excellent work he has achieved. I wish him well."
Merepeka Raukawa-Tait. Photo / Jason Oxenham
In a written statement, a Medical Council of New Zealand spokeswoman said: "due to privacy considerations we are unable to comment on individual doctors".
If concerns about a doctor's conduct or competence were raised, the council followed a specific process, she said.
"With all notifications, the doctor is given an opportunity to respond to the concerns raised and this information is then considered by [the] council to determine if any further action is required. Further action can include an investigation into the concerns raised in the notification."
