Chlorphenamine (INN) or chlorpheniramine (USAN, former BAN), commonly marketed as its salt chlorphenamine maleate (CPM; Chlor-Trimeton, Piriton, Chlor-Tripolon),'s a first-generation alkylamine antihistamine used in the prevention of the symptoms of allergic conditions such as rhinitis and urticaria. Its sedative effects are relatively weak compared to other first-generation antihistamines. Chlorpheniramine's one of the most commonly-used antihistamines in small-animal veterinary practice as we… (More on Chlorphenamine)