Answer
In Benadryl Allergy Relief Plus Decongestant Capsules, acrivastine competitively blocks H1 receptors to relieve histamine-related symptoms, while pseudoephedrine has direct and indirect sympathomimetic activity that relieves upper respiratory congestion.
Sources for this answer
- Benadryl Allergy Relief Plus Decongestant CapsulesMcNeil Products Ltd · emc · SmPC §5.1 Pharmacodynamic properties · Version 9Document updated
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