[1] Penicillin began with Chisato on vocals, Gisho on bass, O-Jiro on drums and both Yuuji and Shaisuke on guitar.
[2] Before anything was recorded however the band's line-up changed to Hakuei on vocals, Gisho on bass, O-Jiro on drums and both Shaisuke and Chisato on guitar.
Their name was taken from the punk rock group "Penicillin Shock" in the manga series To-y and they titled their first album, which was released in 1994 and produced by Kiyoshi of Media Youth,[3] after the fictional band.
[4] Hakuei later stated that when the band started, he wanted to play hardcore punk in a violent and flashy style like Gastunk.
Penicillin made their major label debut in March 1996 with "Blue Moon" on Pioneer LDC.
Their sixth single "Romance" was released on January 15, 1998, and ranked within the top 10 on the Oricon chart for six consecutive weeks, selling over 900,000 copies.