Australians are asking for more than $100 million through online fundraising platform GoFundMe, yet data from the website shows nearly one in five medical campaigns fail to raise anything.
Using data-scraping techniques, the ABC found 3,904 medical-focused fundraising campaigns on the site, with patients asking for an average of $45,000.
Launched in 2010, GoFundMe markets itself as "a place people turn to in times of need".
The website has helped thousands of Australians fund treatment, surgeries and costs not covered by the public health system — sometimes stirring controversy.
Yet the ABC found health campaigns on the site, on average, collect only 19 per cent of their goal.
The ABC's analysis used keyword-based data-scraping techniques to find the most common cases.
It found campaigns focused on treatment for brain conditions asked for the most money, with patients seeking more than $24 million collectively.
But those fundraisers attracted about a quarter of that amount, $6.1 million.
Yet campaigns for brain surgeries were still the most successful, followed by heart conditions ($4.6 million) and lung diseases ($2.3 million).
Others were asking for help to fund highly experimental treatments, overseas programs and even alternative therapies.
For Melbourne mother of three Jelena Magic, it is a bid to save the life of her three-year-old son Marko.
At 18 months of age, Marko was diagnosed with neuroblastoma, a cancer affecting the nerves.
After a relapse, it became life-threatening. So when the family learnt of a vaccine trial in the US that could potentially halt the cancer long-term, they made plans to get Marko there.
The only trouble was the $250,000 price tag.
"I couldn't believe it," Ms Magic said.
"I had no idea that these things cost that much."
Like so many families in similar situations, they turned to GoFundMe.
For the Magics, the first approach to fundraising was using social networks within their Serbian community to promote their cause.
Within a few months they were able to raise about $50,000.
Ms Magic and her husband Andrija regularly posted photos and updates about Marko's health on the website. With each update came a few more shares on social media, and more donations.
"It was not an easy decision to essentially beg people," she said.
"In some cases it feels cathartic [but] sometimes you don't feel like it."
Ms Magic had to give up full-time work to manage Marko's care, in addition to caring for their two other boys, Petar, 7, and Aleksa, 4.
She said it was the little things — as well as big things like their mortgage — that added up during Marko's long treatment plan.
What the Magics did not expect was negative comments online, and the emotional toll from having their fundraising campaign pitted against other equally worthy causes online — even parents of children on the same cancer ward.
"That's one of the worst things," Ms Magic said.
"You have to go into this marketing campaign of 'look at my child he's more needy than other children'. But you do what you have to do."