Hay fever (花粉症) in Japan: season, medicine and clinics

Hay fever (花粉症, kafunsho) in Japan is mostly caused by cedar (スギ) and cypress (ヒノキ) pollen, which typically scatters from about February to April, as of October 2026. The ministry’s manual says a 2019 nationwide survey of ENT doctors and their families put cedar hay fever at 38.8%, about 1 in 3 people, so you are in good company. If you get symptoms every year, the ministry advises starting medicine by about a week before pollen starts in earnest, and see an ENT (耳鼻咽喉科) if over-the-counter medicine is not enough.

What causes hay fever in Japan, and when?

Cedar is the most common cause. Cypress pollen shares antigens with cedar, so it triggers symptoms too. Cedar and cypress are mainly a spring problem, with small amounts in autumn. Other pollens run later:

The exact start of cedar season depends on the temperature in early winter (November and December) and midwinter (January and February). The ministry publishes cedar, cypress and combined pollen data on its pollen information site, which is in Japanese; Tokyo, Osaka and Fukuoka have their own pages. Cedar counts are highest around midday and in the evening, on sunny, warm, dry and windy days, and the day after rain.

If your symptoms come in a different season, the cause may be another pollen. An ENT can run a test to identify it.

Is it hay fever or a cold?

The season overlaps with cold season, and the early symptoms look alike. The ministry’s manual says hay fever often brings itchy eyes and does not cause a high fever, unlike a cold.

Which doctor and medicine?

Start with over-the-counter medicine if symptoms are mild. If they are severe, the ministry recommends an ENT (耳鼻咽喉科) or an eye doctor (眼科). Internal medicine, pediatrics and allergy clinics also treat hay fever.

Clinics prescribe:

• Oral second-generation antihistamines, plus anti-leukotriene medicine if your nose is badly blocked.
• Steroid nasal spray.
• Antihistamine or steroid eye drops. Steroid eye drops can raise eye pressure, so the manual says you need regular eye checkups while using them.

Timing matters. The ministry says starting medicine before pollen scatters, or when symptoms are very mild, is now common (初期療法). Its 2026 guidance says people with symptoms every year should have medicine ready and start it by about one week before pollen starts to scatter in earnest.

To find a clinic that sees patients in English, see English-speaking hospitals and clinics in Japan. To buy or fill medicine, see prescription medicine in Japan. With Japanese public insurance, an insured visit carries the usual copay: 30% for ages 6 to 69.

Is there a long-term treatment?

Allergen immunotherapy is the only treatment that may cure hay fever, says the manual, but the older method had side effects, took a long time and its cure rate was not high. Sublingual immunotherapy (舌下免疫療法), where the allergen is placed under the tongue, has fewer serious side effects and does not require frequent clinic visits. The Tokyo section of the manual states that cedar sublingual drugs went on sale in autumn 2014 and became insured. We could not confirm how long a course lasts or when to start from an official source, so ask the doctor.

How do I reduce exposure?

The ministry’s self-care advice includes:

• Wear a mask and glasses outdoors. In one study, an ordinary mask cut pollen by about 70% and a pollen mask by about 84%. Ordinary glasses cut pollen reaching the eyes by about 40%, and protective glasses by about 65%.
• Wear glasses instead of contact lenses, and a wide-brimmed hat.
• Wash your hands, face and hair when you get home.
• Don’t hang laundry or bedding outdoors.
• Open windows only about 10 cm with a lace curtain, and wash curtains often.
• Choose cotton or synthetic clothing over wool, which collects more pollen.

More guides

• Health checkups in Japan
• National Health Insurance for foreigners