Types of non sedating antihistamines
To find the most current information, please enter your topic of interest into our search box." April 25, 2003 -- Timely research for the start of hay fever season: Despite their higher cost, the newer, so-called "second generation" of more expensive "nonsedating" prescription antihistamines may be no more effective at preventing fatigue and memory lapses than older over-the-counter formulas such as Benadryl.
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.Histamine, acting on H-antihistamines help against these effects, they work only if taken before contact with the allergen.In severe allergies, such as anaphylaxis or angioedema, these effects may be of life-threatening severity.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.Some antihistamines may also be helpful in reducing anxiety, inducing sleep, or at preventing or treating motion sickness.
Antihistamines are classified into two groups – the first-generation (“sedating”) and second-generation (“non-sedating”).
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.
"We're not saying that there's not a difference," says lead researcher Bruce G.