Civil servant Supapan Pullbangyung spends just under half of her salary on caring for her 75-year-old father, who suffers from diabetes and dementia.
Hers is one of many families looking after elderly relatives at a cost that countrywide adds up to just under a third of household income. The number of families facing similar problems will balloon as the population ages at a rate among the fastest in Southeast Asia.
The country's working-age population is expected to shrink by 11% by 2040.
The rising cost of care is an additional burden to households struggling with record debt that is a drag on consumption and stunting the economy.
"I struggled for months and it took a while to adjust," said Ms Supapan, who lives in Nonthaburi province.
Sampao Jantharun (left), 78, assists Somjit Phuthasiri, 90, on a wheelchair as they head to their home at Wellness Nursing Home Centre in Ayutthaya. (Reuters photo)
Looking after her father costs at least 15,000 baht a month, she said, a little less than half what she earns.
A culture of filial piety in which families feel obliged to care for their elderly means more often than not they absorb the expense of looking after parents and grandparents.
A poor savings culture has left many people ill-prepared to help themselves financially in old age, meaning they must rely on working family members.
More than a quarter of the 66 million population has not saved for old age, according to a 2014 survey, one of many factors contributing to the government considering raising the age of retirement from 60 and urging businesses to hire more older people.
"It is going to be a burden on the younger generation," said Sutayut Osornprasop, a human-development specialist at the World Bank.
An elderly man receives help from a nurse during a physical therapy session at Bangkhae Home Foundation in Bangkok April 27. (Reuters photo)
Households caring for elderly relatives spend at least 7,620 baht on them per month, according to the Health Insurance System Research Office, a state agency led by the Ministry of Public Health.
That's more than 28% of the average 2015 monthly household income of 26,915 baht.
Kangsadan Sagulpongmalee, 40, is a lecturer in Phetchaburi province who is caring for her 70-year-old diabetic father. He underwent spinal surgery last December and is recovering at Wellness City, a privately run complex for the elderly on 192 hectares of land near the Ayutthaya.
"The cost has been very high," she said. "My salary earned as a lecturer isn't enough at all. I have to spend my parents' life savings."
Ms Kangsadan plans to move her father to a house near her workplace once he has recovered so she can look after him.
"I'm doing whatever it takes for my parents. It'll be very expensive, but I'll try my best to handle everything."
Elderly people gather before their breakfast at Bangkhae Home Foundation in Bangkok. (Reuters photo)
A lower cost of living in Thailand's rural areas means some who move to the city for work are considering going back to care for elderly parents. Noppasorn Suebsai, 21, is one of them.
"If you live in the countryside where we don't spend as much the cost will be less," said Ms Noppasorn, a Bangkok-based nursing student.
"I don't think I will struggle as much to care for my parents."