Medical expense is relatively cheapter to other countries.
But, it is important to buy some insurance in case you do not have insurance covered in foreign countries.
Japan medication is one of the best in the world.
You will get to see highly skilled doctors if you get sick and so on.
In order to call an ambulance, you just need to hit 119 on the phone and say ‘Kyu kyu desu’ in Japanese because this number directly connects you services for both fire and medical emergencies.