Types of non sedating antihistamines
"The first-generation antihistamines are more sedating, but the distinction isn't as black-and-white as the marketing of the newer products may lead you to believe.The difference between them is really blurred." "Under some circumstances, the nonsedating formulas do cause sedation and in some cases, these sedating formulas do not," he tells Web MD.Additional administration of epinephrine, often in the form of an autoinjector (Epi-pen), is required by people with such hypersensitivities.H-antihistamines can be administered topically (through the skin, nose, or eyes) or systemically, based on the nature of the allergic condition.Sedating antihistamines cause sedation as they are highly lipid soluble and readily cross the blood brain barrier.This sedating activity is sometimes used in managing conditions such as eczema where sleep maybe disturbed due to pruritus.Antihistamines can be further divided into those unlikely to cause drowsiness (non-sedating antihistamines) or those likely to cause drowsiness (sedating antihistamines).Antihistamines are used in the treatment of allergic reactions, colds, hay fever, hives, and insect bites and stings.
Antihistamines are classified into two groups – the first-generation (“sedating”) and second-generation (“non-sedating”).
So concludes a new study published in the current issue of Journal of Allergy and Clinical Immunology in which researchers compared 18 previous trials investigating antihistamine-caused sedation levels in 1,500 people between ages 8 and 81.
Most of the studies reviewed used doses that were twice the recommended amount -- 50 milligrams -- of diphenhydramine, the active ingredient in Benadryl and other first-generation "sedating" allergy medications.
Agents where the main therapeutic effect is mediated by negative modulation of histamine receptors are termed antihistamines; other agents may have antihistaminergic action but are not true antihistamines.
In common use, the term "antihistamine" refers only to H In type I hypersensitivity allergic reactions, an allergen (a type of antigen) interacts with and cross-links surface Ig E antibodies on mast cells and basophils.