Which of the following anticholinergic agent does not cross the blood brain barrier?
(A) Glycopyrrolate (B) Atropine (C) Hyoscine butylbromide (D) Hyoscine hydrobromide
(D) Answer- D. Hyoscine hydrobromideGlycopyrrolate is a synthetic quaternary anticholinergic, which doesn't cross the blood brain barrier and completely lacks central effects.