Hisanaka Pharmaceutical, which Kotaro attracted as a potential sponsor for Franchouchou is based on Hisamitsu, a real-life Saga-based pharmaceutical company. In particular, their "Saganship Z" dermal patches are based on Salonpas, their most famous brand.
During the scene where the girls from the band Franchouchou fool around putting on dermal patches, there is an on-screen warning in "Do not try this at home" style saying that it is dangerous to use dermal patches without prescription And these must be applied by medical professionals such as doctors or nurses. (Putting this kind of patch counts as practicing medicine).