List of sedating antihistamines
All antihistamines work in the same way: by competing with histamine to prevent or reduce the characteristic signs and symptoms of an allergic reaction: swelling, tearing, itching, and increase in bronchial and other secretions.In addition to oral dosage forms, antihistamines come as creams, lotions, nasal sprays, and eye drops; the latter to relieve symptoms associated with allergic conjunctivitis.
They are often used if other agents are ineffective or intolerable.Their main benefit is they primarily affect peripheral histamine receptors and therefore are less sedating.However, high doses can still induce drowsiness through acting on the central nervous system.Other types of allergy drugs include: Corticosteroids: These come as nasal sprays, topical creams and ointments, tablets, injectables and eye preparations. Mast cell stabilizers: These can help prevent allergic reactions from happening when taken regularly.During an allergic reaction, mast cells release histamine and other substances.Some second-generation antihistamines, notably cetirizine, can interact with CNS psychoactive drugs such as bupropion and benzodiazepines.-antihistamines are among first-line therapy to treat gastrointestinal conditions including peptic ulcers and gastroesophageal reflux disease. Most side effects are due to cross-reactivity with unintended receptors.
Cimetidine, for example, is notorious for antagonizing androgenic testosterone and DHT receptors at high doses.
Examples include: receptors are primarily found in the brain and are inhibitory autoreceptors located on histaminergic nerve terminals, which modulate the release of histamine.
Histamine release in the brain triggers secondary release of excitatory neurotransmitters such as glutamate and acetylcholine via stimulation of H Research into these drugs led to the discovery that they were H1 antagonists and also to the development of H2 antagonists, where H1 antihistamines affected the nose and the H2 antihistamines affected the stomach.
These allergy drugs relieve allergy symptoms but cause drowsiness and other side effects, including dry mouth.
Newer antihistamines are said to be non-sedating, although some users may experience drowsiness even from these.
Mild allergy symptoms include itchy, watery eyes, a runny nose, scratchy throat and a rash.