excitability, dizziness and anxiety. Infrequent ADRs include:  tachycardia  and/or  palpitations . Triprolidine IUPAC Name:  2-[(E)-1-(4-methylphenyl)-3-pyrrolidin-1-yl-prop-1-enyl]pyridine Structural Formula Chemical Formula: C19H22N2 Medical Usage: Triprolidine (Actidil, Myidil) is an  over-the-counter   antihistamine  with  anticholinergic  properties. It is used to combat the symptoms associated with  allergies  and is sometimes combined with other  cold  medications designed to