For a Filipino man visiting Tokyo in May last year, the tour of the capital was supposed to be a fun sightseeing trip.

But the man collapsed after suffering a cerebral hemorrhage and was rushed to NTT Medical Center Tokyo in Shinagawa Ward for an emergency operation.

Fortunately, the surgery saved his life. But the trouble didn’t stop there. As a tourist, his medical costs were not covered by Japan’s national health insurance system, pushing his medical bills to an eye-popping ¥5.4 million.

“If you are covered by the health insurance system, you may need to pay just ¥100,000 or ¥130,000 or so even if the actual cost is something like ¥2 million to ¥3 million,” said Isao Ebihara, a medical coordinator for foreign patients at NTT Medical Center Tokyo. “But if you are a tourist not covered by any insurance, you have to shoulder all of the actual costs on your own. Few tourists can pay ¥1 million or ¥5 million in cash, particularly those from developing countries.”

The Filipino man, whose name is being withheld to protect his privacy, could not immediately pay the bill, which prompted the Philippine Embassy in Tokyo to temporarily cover part of the expenses.

The case is just one of many that hospitals across the nation are seeing amid the tourism boom.

Tourists have more than quadrupled from 6.79 million in 2009 to 28.69 million in 2017, partly thanks to the easing of visa conditions for visitors from China, Thailand, Malaysia, India, the Philippines, Vietnam, Indonesia and Brazil, according to the Japan Tourism Agency. The government aims to boost that figure to 40 million by 2020 and 60 million by 2030, or three times the level in 2015.

But the growing influx is likely to put a greater strain on Japan’s hospitals as many patients from overseas arrive without insurance, experts say.