Antihistamines (H1 inhibitors) are of value in the treatment of allergic rhinitis and urticaria.

Examples of sedating antihistamines
  • Chlorpheniramine

As well as being sedating these antihistamines have some antimuscarinic properties (e.g. urinary retention, dry mouth).

Examples of non-sedating antihistamines
  • Loratidine
  • Cetirizine

Of the non-sedating antihistamines there is some evidence that cetirizine may cause more drowsiness than other drugs in the class.