The Home Page of Pollinosis by Allergy Research Group,
Department of Otorhinolaryngolgy, Jikei Medical School

Revised on June 24, 2000

Welcome to our home page on pollinosis.

This page is made for the patients suffering from Japanese cedar pollinosis.
We provide some information about this disease including daily pollen counts in Tokyo area. Since there is little knowledge of the non-Japanese patients suffering from this disease. We would welcome to get information in order to have better treatment for you.

New Information

(June 24, 2000)
The web site of "World Pollen Calendar" was built recently and our site is now linked as an information of pollen in Japan.

Several graphs are introduced in Japanese now in our web site, and will be translated into English soon.

1. Pollen counts of the spring of 2000 in Tokyo. @Counted pollens were divided to cedar, cypress, and non-cedar non-cypress pollens.

2. Total pollen counts of cedar and cypress of the spring from 1987 to 2000 in Tokyo.

3. Comparison of the pollen counts of the data with Durham device and automatic realtime counter. @Cedar and cypress pollens are counted with the realtime counter automatically by LAZER method.

4. In Japan pollens are counted in over 400 points. Some of them can be seen in web sites. @See LINK of web sites of pollen informations.

(February1, 1997)
1. In Tokyo total number of Japanese cedar pollen (JCP) will scatter about 2900-3300 pollens /cm2 /season which are about 1.5 times as high as average. JCP has not officially begun to release in all around Japan, but will start to release at February 7-8 in Tokyo which day is a week earlyer than average.
2. Prophylactic drug threapy is recommended to the patients with severe or moderate symptoms. Tomorrow is not too early to begin prophylactic drug therapy in Toyo. These kind of drugs have less side effects (less sleepy, less dry feeling in mouth) and are prescribed only by physicians.
3. Prophylaxis of pollinosis is not only by taking drug but also by control of life style.(See FAQ #5)


1. What is pollinosis ?
Pollionosis is a disease of allergic rhinitis and allergic conjunctivitis which are caused by several pollens. Pollinosis with Japanese cedar pollens is called to be one of the three major pollinosis in the world because of severe symptoms and a lot of patients. In Japan about 50 kinds of pollinosis have been reported.

2. Which pollens cause pollinosis ?
It depends on the place you live because some pollens are unique in some place. In Japan Japanese cedar pollen (JCP) is most important except Hokkaido island. Cypress pollen which is relevant to cedar pollen is also important in Japan which scatter later and after cedar pollen season. Cockfoot is also important in Japan as in Europe which cause symptoms like several similar pollens (sweet vernal grass, Bermuda grass, cockfoot, meadow fescue, rye-grass, timothy, common reed , meadow grass, redtop, Johnson grass, brome grass, cultivated rye, velvet grass, cultivated oat, cultivated wheat, meadow, foxtail, Bahia grass). Ragweed pollens disperse in August in Japan. This pollen is less important in Japan than in North America.

2. Why have I begun to be suffered from pollinosis in Japan ?
First of all, you did not have symptoms with JCP because JCP is unique in Japan. After you came to Japan, you have been sensitized with JCP and begun to have symptoms. Usually, it takes over 2 years to be sensitized and have symptoms.

3. Which day of pollen begins to release ?
Like cherry blossoms JCP front moves from south to north. JCP begin to release from the last week of January in south islands of Japan and from mid April in north island (south Hokkaido). The end of JCP scattering is early April in south island and early May in north. In Tokyo aria JCP begin to scatter from about February 14 to late April.

4. How to diagnose it ?
In order to diagnose Japanese cedar pollinosis, you need to have symptoms during pollen season. To confirm the diagnosis, we check sensitized allergens by skin test, nasal provocation test, and serum IgE test.

5. How to treat pollinosis
A guideline for allergic rhinitis (including pollinosis) by Japan Allergy Society recommends 4 kinds of therapies which are instruction of self control, drug therapy, allergen-specific immunotherapy and operation therapy. We think the standard therapy now is self control with drug therapy. Self control is instructed to prevent contact to pollens (and other allergens) by staying indoor, putting on a mask and a pair of goggle, and keeping well controlled life style. In recent 10 years prophylactic drugs are commonly used and several new drugs have been developed. In order to prevent severe symptoms, a prophylactic drug is used for the patients suffering from pollinosis about 2 weeks before the day of pollen release. For this purpose prediction of the beginning day of pollen dispersing and forecast of total pollen counts are iuseful.

Please send your comments or question

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