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Updated: Aug 4, 2026

Murine Model of Allergen Induced Asthma
Published on: May 14, 2012
The comparative bronchodilator properties of alkyl quaternary salts of promethazine
Abstract:
Several salts of thiazinamium, a quaternary analogue of promethazine, administered by aerosol, possessed equipotent anticholinergic activity in anesthetized guinea pigs but the duration of this effect differed somewhat. N-Butyl substitution in the side chain, but not the corresponding ethyl or n-propyl substitutions, reduced the aerosol anticholinergic potency and duration. There was also a tendency for a corresponding reduction in antihistaminic activity with different alkyl substitutions and for a greatly reduced duration of this effect.
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