New Apps Help Users Handle Heatstroke in Japan; People Can Receive Alerts, Assess Physical Condition

The Yomiuri Shimbun

12:35 JST, August 2, 2025

The government and related academic organizations have launched smartphone apps that provide alerts when intense heat conditions occur or can assess the severity of someone’s heatstroke conditions. The move comes amid a surge in the number of people being taken to the hospital as scorching temperatures persist.

The Japan Meteorological Agency in April launched the Digital AMeDAS app, which notifies users when heatstroke alerts are issued for the areas they have registered with the app. These alerts are normally released at around 5 p.m. when the wet bulb globe temperature (WBGT) is predicted to be 33 or higher the following day, and repeated at about 5 a.m. on the day the alert applies.

Another app, JoinTriage, can help people understand the severity of someone’s heatstroke condition. The app, provided by the Japanese Association for Acute Medicine, allows users to enter information on symptoms such as headaches and dizziness, as well as information including age, gender and pre-existing conditions. The app can provide advice on whether to seek medical attention or call an ambulance.

In the week ending July 27, 10,804 people nationwide were taken to hospitals due to heatstroke, according to the Fire and Disaster Management Agency.

“For the elderly who are not familiar with smartphones and are at a high risk of suffering heatstroke, their family members or caregivers are encouraged to use these apps,” said Nippon Medical School Prof. Shoji Yokobori.