Answer
The glycopyrronium component of glycopyrronium + neostigmine metilsulfate penetrates the blood-brain barrier poorly because its quaternary ammonium moiety makes it highly ionised at physiological pH.
Sources for this answer
- Glycopyrronium Bromide and Neostigmine Metilsulfate 0.5mg/2.5mg per ml Solution for InjectionMartindale Pharma, an Ethypharm Group Company · emc · SmPC §5.1 Pharmacodynamic properties · Version 3Document updated
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