↓が理由なのかな?と思ってる https://en.wikipedia.org/wiki/Orexin
>Orexin neurons strongly excite various brain nuclei with important roles in wakefulness
>including the dopamine, norepinephrine, histamine and acetylcholine systems
https://en.wikipedia.org/wiki/Bilastine#Pharmacology
>No anticholinergic adverse events were observed in the clinical trials with bilastine.
ほとんどの抗ヒスタミンにある抗コリン作用(ガラと真逆の作用)が無い?
興味を引くね