Sedating antihistamine abuse simplified dating
This selectivity significantly reduces the occurrence of adverse drug reactions, such as sedation, while still providing effective relief of allergic conditions.
The reason for their peripheral selectivity is that most of these compounds are zwitterionic at physiological p H (around p H 7.4).
As such, they are very polar, meaning that they do not cross the blood–brain barrier and act mainly outside the central nervous system.
However, some second-generation antihistamines, notably cetirizine, can interact with CNS psychoactive drugs such as bupropion and benzodiazepines.-antihistamines are second-generation antihistamines informally labeled third-generation because the active enantiomer (levocetirizine) or metabolite (desloratadine and fexofenadine) derivatives of second-generation drugs are intended to have increased efficacy with fewer adverse drug reactions.
These antihistamines are more selective on peripheral H1 receptors and have a lower affinity for cholinergic and alpha-adrenergic receptor sites, which reduces the risk of anticholinergic and central nervous system side effects.
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.
These side effects can greatly increase the risk of falls and fall-related injury, with the impact of even one fall in an older adult potentially having tremendous negative consequences, including diminished quality of life and loss of independence.The most common adverse effects noted for second-generation agents include drowsiness, fatigue, headache, nausea and dry mouth.-antihistaminergic drugs and are relatively inexpensive and widely available.They are effective in the relief of allergic symptoms, but are typically moderately to highly potent muscarinic acetylcholine receptor (anticholinergic) antagonists as well.An estimated 25% of patients over the age of 65 have some existing cognitive decline, which may not always be obvious or recognized by others.5 However, when given highly anticholinergic medications, these patients may present with symptoms resembling those of dementia, which may lead to an inappropriate diagnosis of clinical dementia.Levocetirizine dihydrochloride is a type of medicine called a non-sedating antihistamine.
It works by preventing the actions of histamine - a substance produced by the body when it reacts to a foreign substance such as pollen or pet fur (an allergen).