Search results
Results From The WOW.Com Content Network
A subsequent 1990 study found that the elimination half-life of diphenhydramine was 5.4 hours in children, 9.2 hours in young adults, and 13.5 hours in the elderly. [7] A 1998 study found a half-life of 4.1 ± 0.3 hours in young men, 7.4 ± 3.0 hours in elderly men, 4.4 ± 0.3 hours in young women, and 4.9 ± 0.6 hours in elderly women. [84]
The shorter elimination half-life of diphenhydramine (4–8 hours) compared to doxylamine may give it an advantage over doxylamine as a sleep aid in this regard. [27] Antihistamines like doxylamine are sedating initially but tolerance occurs with repeated use and can result in rebound insomnia upon discontinuation. [7] [28]
Polonium in the body has a biological half-life of about 30 to 50 days. Caesium in the body has a biological half-life of about one to four months. Mercury (as methylmercury) in the body has a half-life of about 65 days. Lead in the blood has a half life of 28–36 days. [29] [30] Lead in bone has a biological half-life of about ten years.
Loratadine's peak effect occurs after 1–2 hours, and its biological half life is on average eight hours (range 3 to 20 hours) with desloratadine's half-life being 27 hours (range 9 to 92 hours), accounting for its long-lasting effect. [34] About 40% is excreted as conjugated metabolites into the urine, and a similar amount is excreted into ...
Chlorphenamine acts primarily as a potent H 1 antihistamine. It is specifically a potent inverse agonist of the histamine H 1 receptor. [22] [23] The drug is also commonly described as possessing weak anticholinergic activity by acting as an antagonist of the muscarinic acetylcholine receptors.
Antihistamines are drugs which treat allergic rhinitis, common cold, influenza, and other allergies. [1] Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provides relief from nasal congestion, sneezing, or hives caused by pollen, dust mites, or animal allergy with few side effects. [1]
Cetirizine is a second-generation antihistamine used to treat allergic rhinitis (hay fever), dermatitis, and urticaria (hives). [5] It is taken by mouth. [6] Effects generally begin within thirty minutes and last for about a day. [6] The degree of benefit is similar to other antihistamines such as diphenhydramine, which is a first-generation ...
Antihistamine Dose a Time to peak Half-life b Metabolism Anticholinergic Diphenhydramine: 50 mg 2–3 hours 2–9 hours CYP2D6, others Yes Doxylamine: 25 mg 2–3 hours 10–12 hours CYP2D6, others Yes Hydroxyzine: 25–100 mg 2 hours 20 hours ADH, CYP3A4, others No Doxepin: 3–6 mg 2–3 hours 17 hours c: CYP2D6, others No (at low doses ...