Eisai: The First 70 Years - History of Eisai -

  • Corporate Chronology
  • The Story of Eisai
  • Eisai's Founder, Toyoji Naito
  • R&D Archives
  • History Gallery
  • Chapter 1
  • Chapter 2
  • Chapter 3
  • Chapter 4
  • Chapter 5
  • Chapter 6
  • Chapter 7

The Story of Eisai: Chapter 2 Nihon Eisai Established 1938–1954

Producing injections at the Honjo Plant (the former Nihon Eisai site) just after World War II

Nihon Eisai Co., Ltd. is established just days before the Pacific War.It later merges with the Sakuragaoka Lab to comply with wartime regulations.

The Sakuragaoka Laboratory continued to create a string of hits starting with its 1938 launch of Japan's first commercial vitamin E product Juvela, which was developed from wheat germ oil extract. Juvela was closely followed by other successes such as the sanitary tampon Sampon and La Vende, a medicated talcum powder. At this point, the Sakuragaoka Laboratory research team had swelled to 74 members and outgrown its Tokyo facility. To expand further, Toyoji purchased the Tsurumaki Silk Mill just north of Tokyo in Honjo, Saitama, and on December 6, 1941, established Nihon Eisai Co., Ltd.—Eisai's second incarnation—with ¥180,000 in capital. In just two days, the Pacific War would begin. Toyoji was 53 years old.

In May 1942, the Japanese government issued a public declaration under its wartime national policy, enforcing industrial adjustments aimed at streamlining Japanese industry. Under the legislation, all companies with ¥500,000 or less in capital were to be either consolidated or closed down. Accordingly, Sakuragaoka Laboratory Co., Ltd. and Nihon Eisai Co., Ltd. were merged together on December 26, 1944, with the new company retaining the name of the latter—Nihon Eisai Co., Ltd.


Introducing family planning to Japanese society

When Sampoon was first launched in 1948, contraception was still a poorly understood subject and even when Toyoji succeeded in gaining official government approval for the product, it was only as a drug to be used for the prevention of venereal disease. The following year, however, in 1949, an amendment was made to Japan's Eugenic Protection Act to allow abortions to be performed. Contraceptives were also legalized and the concept of family planning using Sampoon was introduced to the public to help address social issues related in part to Japan's postwar baby boom.

(left) Sampoon advertisement from 1951

Eisai Advertising Through the Years

The war's end sees Nihon Eisai return from military industry to civilian demand.Sampoon is launched nationwide following the country's postwar baby boom.

The tide of war soon turned against Japan and air raids commenced on the mainland. It was now orders for dried-food field rations coming in from the Japanese military that were keeping Nihon Eisai afloat. Public perception of the company slowly shifted from pharmaceutical manufacturer to food processing plant for the Japanese military. When the war finally ended on August 15, 1945, Nihon Eisai decided to shift its focus entirely from military to civilian demand as a peacetime industry. At the time, Japan was also experiencing its postwar baby boom. Toyoji came across an article on the contraceptive properties of phenyl mercuric acetate (PMA) in the British medical journal The Lancet and, based on this concept, successfully developed the vaginal contraceptive suppository Sampoon. Following Sampoon's launch in 1948, Toyoji traveled around the country to give lectures on the concept of family planning, as contraception was still a taboo topic in Japan at the time.

Eisai Nihon's dedicated team of researchers circa 1953

Nihon Eisai develops the first products in its popular Chocola series and changes its name from Nihon Eisai to Eisai as we know it today.

In the first half of 1951, after overcoming Japan's chaotic postwar years, the company finally turned its first profit since establishment. Furthermore, Nihon Eisai also developed what would become the first in its hit Chocola vitamin series, which would sustain the company for many years to come—Chocola A. The vitamin A product was used to treat a wide range of symptoms, including night blindness, dry skin disorders, and malnutrition in children. On the heels of strong, extended Chocola A sales, Nihon Eisai followed up its success with the launch of additional vitamin C and D products as well, respectively, Chocola C and Chocola D.

In 1953, Nihon Eisai enjoyed rapid growth through the launch of several new products, including the anti-asthmatic Asthphyllin and gastric ulcer treatment Methaphyllin. Two years later, in May 1955, a decision was made at a general shareholders' meeting to change the company name from “Nihon Eisai Co., Ltd.” displayed in Chinese characters to “Eisai Co., Ltd.” in simpler, katakana script. Two of the reasons for this change were that a shorter, easier-to-write name would be more readily remembered and more efficiently written. Nihon Eisai had begun as a manufacturer of products for the wartime military. Eisai, however, was able to survive the postwar chaos and help welcome in Japan's coming period of strong economic growth under a new company name through shifting its focus in response to the huge changes taking place in the country at the time.

Origin of the Eisai Logomark


Why did Toyoji name his hit vitamin series Chocola?

Chocola* is a vitamin series with an interesting name. Inspired by the popularity of cola drinks on the market during his years at the Sakuragaoka Laboratory, Toyoji had first registered the name “Chocola” as a trademark with the intention of one day creating his own chocolate-flavored drink. As Toyoji was looking for a brand name for his new vitamin series that would be easy for people and, in particular, children to remember, he decided to use the name “Chocola” for the series instead. Chocola has gone on to become a household name in Japan and Eisai has used it continuously ever since the very first Chocola product, Chocola A.

* Chocola products do not contain chocolate or cola-derived ingredients.