Answer
In Multi-Action ACTIFED Tablets, pseudoephedrine acts directly and indirectly on the sympathetic nervous system to relieve upper respiratory congestion, while triprolidine competitively blocks histamine H1 receptors to relieve histamine-related symptoms and has mild central nervous system depressant effects that may cause drowsiness.
Sources for this answer
- Multi-Action ACTIFED TabletsMcNeil Products Ltd · emc · SmPC §5.1 Pharmacodynamic properties · Version 9Document updated
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