WATCH: Teenager breaks European cancer treatment fundraising record

The dramatic cash boost following a viral post has helped pay for potentially life-saving therapy in the US for an "overwhelmed" Shauntelle Tynan.

The total has hit more than 700,000 euro (£594,000) and will allow the family to cover at least a year's potentially life-saving care.

Her delighted mother Leona Tynan said it was the most successful fundraising campaign ever run in Ireland and in the top 20 in the world.

"It is the fastest amount ever earned in Europe as well," she said.

"It is just incredible."

Shauntelle Tynan, 18, has said she had been told by her Texas-based doctor that her chances of recovery depended on how long she could spend in the US.

The money was raised for the Co Carlow woman on crowdfunding website gofundme.com in a matter of days.

Before that, the family had spent more than a year trying to raise the money.

Leona Tynan said: "To know that whatever she needs is there, there are no words to describe how we feel."

The family is set to travel to the US soon and will be there for at least a year.

Shauntelle Tynan said it had been an incredible experience.

She told donors: "I would never have thought this support would be possible.

"Everyone came together and helped me so much, I cannot thank you enough."

Ms Tynan added: "I have been crying all morning.

"I was not expecting half, even a quarter of the support I got."

Ms Tynan was diagnosed nearly two years ago with a rare form of multi-system Histiocytosis X/Langerhans cell histiocytosis (LCH).

Since her diagnosis the cancer has spread to her gastrointestinal system, colon and skin.

Doctors in the US have said she needs to come to America for at least 12 months to survive.

She said she would have to travel back to Texas for five years even after she was in remission.

Her campaigning family and friends have used a motorbike run and other initiatives to raise money.

But this huge lift in funds has dramatically changed her prospects.

Ms Tynan used her Facebook account to thank those who contributed sums from a few euro to several thousand.

She added: "I just wanted to say thank you so much to everyone for all of the support.

"The last 38 hours has been a place of love and the people of Ireland have truly came together to help me get better, and for that I'm truly thankful.

"There has been few haters but millions of lovers, and each person showing positivity helps us through each day and we are truly over the moon. The good always outshines the bad."