Penicillin, a cornerstone of the visual kei movement during the 1990s, survived the very aesthetic they had championed by sustaining consistent output even while switching imprints with greater frequency than Deep Purple rotated singers. Several university students from Kanagawa launched the group in 1992; its early configuration briefly featured guitarist Shaisuke, who would later join Baiser. The lineup eventually settled into the quartet of Hakuei on vocals, Gisho on bass, O-jiro on drums, and Chisato on guitar. Their first release arrived in 1994 with the EP Penicillin Shock—the sole recording to include Shaisuke—followed that same year by the full-length Missing Link and the pair of 1995 EPs Earth and Into the Valley of the Dolls. A brief contract with Pioneer yielded the instrumental set Indwell in 1996, packaged with a VHS containing promotional clips for every track, and two subsequent studio efforts, Vibe (1996) and Limelight (1997). The 1998 single Romance moved 900,000 units. Beginning in 1996 the members also pursued occasional solo endeavors.
East West Japan signed Penicillin in 1998, a tenure complicated when the band conceived, filmed, and performed a rock opera drawn from Shakespeare’s Hamlet. They additionally issued the non-themed albums Ultimate Velocity (1998) and Union Jap (2000) plus two compilations before visual kei’s commercial decline prompted the label to drop them in 2001. Operating independently thereafter, they secured a deal with an Avex subsidiary in 2002 and advanced to the parent company in 2005, producing five further studio albums by the close of that year alongside numerous ancillary releases. At their fifteenth anniversary in 2007, following the album Blue Heaven, Gisho departed; the remaining members continued as a trio and transferred to Nippon Crown in February 2008.
