A new treatment drug for obesity has been put on sale in Japan, allowing doctors to prescribe the GLP-1 receptor agonist for highly overweight patients.

Wegovy was developed by a Danish pharmaceutical firm. The drug received approval from the Japanese authorities last year and its sale began on Thursday.

A physician specialized in obesity treatment at Chiba University Hospital prescribed Wegovy for a female outpatient in her 60s.

The drug needs to be injected into the belly by patients themselves, so she made a shot following the instruction from a nurse. The doctor then advised her how to improve her dietary life and physical activity.

Wegovy is covered by health insurance in Japan only if the person is diagnosed with obesity and suffering from obesity-related health problems, such as high blood pressure.

But there are concerns that the drug could be misused for cosmetic or diet purposes. There are an increasing number of cases where diabetes drugs which contain similar substances as Wegovy are used inappropriately for such purposes.

The health ministry has released guidelines on Wegovy, urging people not to use it other than for obesity treatment.

Doctor Ono Hiraku at Chiba University Hospital said that patients with serious obesity have been waiting a long time for Wegovy, but the drug could cause side effects, such as low blood pressure, if it is used for cosmetic and other inappropriate purposes.

He stressed that the drug should be prescribed with caution.