The high price of insulin across the country is forcing some families with type 1 diabetes to go north to buy the medication. From 2012 to 2016, the price of insulin nearly doubled in the U.S. — and last weekend, about a dozen people took a bus 817 miles from Minneapolis, Minnesota, to London, Ontario, to buy the life-saving drug.

"For us, insulin is like air — it's like oxygen, we need it," said Deb Souther, who has lived with Type 1 diabetes for 46 years.

Souther says she uses three vials of insulin a month. Even with insurance, she's paying more than $700 a month for medicine she can't live without. "It is very very worrisome, even with insurance, if you only have one vial or two vials sitting in your refrigerator," she said.

A lot of people on the bus traveled more than 800 miles. But for them, it's not about the miles — it's about the message. That's why they drove all the way to London, Ontario, where insulin was developed nearly a century ago.

"Getting diagnosed today in 2019 in America with type 1 diabetes — it is a death sentence for some people," said Quinn Nystrom, who coordinated the trip. This is the second caravan to Canada in the last two months. In the U.S., one vial of the drug costs $340, Nystrom said — but in Canada, it's just $30.

"It's because I bought it in Canada," she said. "That's the only difference."

Insulin is cheaper in Canada primarily because the country has public health care, so the government negotiates pricing with drug companies and caps prices. In the U.S., drug makers negotiate individually with private insurance companies and the uninsured pay list price. Approximately 7.5 million Americans rely on insulin to stay alive. The drug is largely supplied by three companies, who all offer patient assistance programs.

Novo Nordisk, one of those three companies, told CBS News in a statement that "we recognize that our healthcare system is broken ... we know more must be done to ensure insulin affordability and we are committed to being part of the solution."

Some states are taking their own steps to lower the cost. Florida passed a law that would allow large batches of drugs to be legally imported from Canada into the state, and Colorado capped insulin costs at $100 dollars per monthly supply.

Nystrom believes the issue shouldn't be politically divisive. "There's Republicans who are diabetics, there's Democrats who are diabetics and all of us struggle to afford insulin ..." she said. "To me this is a human rights issue."

Nystrom says she's lucky to be able to make the trip, because many people couldn't afford to miss work.

"Coming to Canada is not a long-term solution," she said. "Coming to Canada is putting a Band-Aid on a gunshot wound."