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Anti-histamines

In the strictest sense, anti-histamines are H1 histamine receptor antagonists. This means they block histamine from reacting with the H1-receptors, countering the effects of Histadelia that would normally result from H1 receptor stimulation. Thus, anti-histamines are often prescribed to relieve the symptoms of hayfever, rashes, and allergies. Examples of these type of anti-histamines are:

NameTradenames /
Uses
Structure3D Chime

Diphenhydramine

Benadryl

Benadryl, Dimederol, Nytol

Used to treat colds and flu, and as a sleeping pill.

Benadryl

Loratadine

Clarinase

Claritin, Claritin-D, Claritine, Clarityn, Clarityne, Fristamin, Lomilan, Symphoral, Roletra, Rinolan, AllergyX, Alavert or Clarinase

Used to treat allergies.

Loratadine

Meclizine

Bonine

Bonine, Antivert

Used to prevent motion sickness, vertigo and nausea.

Meclizine

Quetiapine

Seroquel

Seroquel, Ketipinor

Used to treat psychosis, schizophrenia, and acute manic episodes associated with bipolar disorder.

Quetiapine

It is now possible to get other histamine receptor antagonists. For example, a number of H2 blockers are available which are used to reduce stomach acid, or in the teatment of stomach ulcers. These include: Cimetidine (Tagamet), Famotidine (Pepcidine, Pepcid), and Ranitidine (Zinetac, Zantac). H3 blockers are used to make people more awake, by allowing more histamine to be produced, therefore triggering more H1 receptors.