These receptors both receive histamine as a messenger, but the meaning conveyed is different.
Antihistamines are used to treat the sneezing, runny nose, and itchy eyes of allergies and allergic rhinitis, as well as allergic skin reactions and anaphylactic reactions to insect stings and certain foods.
Histamine irritates and inflames the airways to produce sneezing and mucus production.
Antihistamines attach to the areas on cells that histamines attach to, thereby blocking the allergic response.
Non-sedating antihistamines are helping to improve the lives of countless people who suffer from the symptoms of serious allergic reactions.
Antihistamines are prescribed or recommended for infants, children, and adolescents with allergies and allergic rhinitis.
Depending on the type of allergy, oral antihistamines may be taken regularly or seasonally to combat responses to allergens.
Stomach pain acid secretion increases; small intestine contracts with crampy pain Respiratory - nose swelling, congestion, sneezing and wheezing.
Anxiety and agitation with diffuse, deep, odd body sensations:"..bones are on fire", "I feel weird all over", "...a deep pricking, crawling sensation...".