The side effect profile, which also determines the uses of the drugs, will vary by chemical class.
The alkylamines include brompheniramine (Dimetapp) and chlorpheniramine (Chlor-Trimeton.) These agents cause relatively little sedation, and are used primarily for treatment of allergic reactions.
receptor, helping to relieve from allergic reactions.
The isomerism is a significant factor in the activity of the agents in this group.First-generation antihistamines include diphenhydramine (Benadryl), carbinoxamine (Clistin), clemastine (Tavist), chlorpheniramine (Chlor-Trimeton), and brompheniramine (Dimetane).However, a 1955 study of "antihistaminic drugs for colds," carried out by the U. Army Medical Corps, reported that "there was no significant difference in the proportion of cures reported by patients receiving oral antihistaminic drugs and those receiving oral placebos.H-antihistamines can be administered topically (through the skin, nose, or eyes) or systemically, based on the nature of the allergic condition.The authors of the American College of Chest Physicians Updates on Cough Guidelines (2006) recommend that, for cough associated with the common cold, first-generation antihistamine-decongestants are more effective than newer, non-sedating antihistamines.As such, they are very polar, meaning that they do not cross the blood–brain barrier and act mainly outside the central nervous system.