| Year | Detail |
| 1921 |
Busaburo Otsuka established Otsuka Seiyaku Kogyo-bu (renamed Otsuka Pharmaceutical Factory, Inc. in 1940). |
| 1953 |
Otsuka launched its first over-the-counter medicine, Oronine Ointment. |
| 1965 |
The company entered the energy drink market and launched Oronine Ointment. |
| 1973 |
The Group established Thai Otsuka Pharmaceutical Co., Ltd. as a joint venture with local capital. |
| 1989 |
Otsuka America, Inc. was founded. |
| 1998 |
Otsuka Pharmaceutical Europe Ltd. Was founded. |
| 2006 |
The product ABILIFY was launched in Europe, and Interpharma Praha, a.s. was established in the Czech Republic. |
| 2017 |
Otsuka group Health Declaration established. |
| 2019 |
Otsuka Business Support Co., Ltd. was established as a shared service company for Otsuka group companies. |
| 2023 |
Pharmavite, a U.S. subsidiary of Otsuka Pharmaceutical, acquired Bonafide Health. |
| 2024 |
Korea Otsuka Pharmaceutical launched Soy Bar "SOYJOY". |