Hydroxyzine is a first-generation sedative antihistamine , which means it has side effects similar to Benadryl . It is marketed under the brand names Atarax and Vistaril, but is also available in generic form. Hydroxyzine was originally developed as a sedative in the 1950s, but it was found to have significant antihistamine properties.
Hydroxyzine for allergies
Hydroxyzine is commonly prescribed to treat a variety of allergic conditions such as hives , but it is also often used to treat itching , anxiety, insomnia, and nausea and vomiting . The dose of hydroxyzine depends on the condition being treated, although the usual dose is 25 to 50 milligrams every six hours. Hydroxyzine is also used for children, although the dose is calculated based on the child's weight. However, the effects of sedation and drowsiness can lead to the prescription of one of the second-generation antihistamines, such as Xyzal (levocetirizine).
How does it work
Hydroxyzine works by blocking, binding to H1 receptors and decreasing the activity of histamine. Histamine allows more fluid to escape from capillaries into tissue, and it is this fluid that you experience as a runny nose and watery eyes when you have an allergic reaction. Histamine also causes swelling and the formation of wheels in the form of a rash.
By blocking the H1 receptor, hydroxyzine is effective against these allergy symptoms. It can also help when the itching (itching) is caused by an allergy.
But hydroxyzine also enters the brain, where it causes drowsiness and sedation. These effects can be undesirable in the treatment of allergies.
Second-generation hydroxyzine-based antihistamines
The active metabolite of hydroxyzine is cetirizine (Zyrtec) , which is sold over the counter as a low-sedating antihistamine.
The active isomer of cetirizine is levocetirizine (Xyzal), which is available by prescription only and is now available in generic form. It does not enter the brain as quickly as hydroxyzine and therefore does not induce the same sedative effect, nor does it have the sedative effect of hydroxyzine for the same reason.
Zyrtec and Ksizal are more suitable for the treatment of allergic rhinitis than hydroxyzine because they have fewer side effects and a longer duration of action. They are also effective in treating hives and itching.
Zyrtec and Ksizal are not effective in treating anxiety, insomnia, or nausea and vomiting, conditions for which hydroxyzine or other first-generation antihistamines may be prescribed. (Although hydroxyzine is a 50-year-old drug, it is still useful for treating a variety of conditions.)
A 2009 review of Xyzal (levocetirizine) studies found that 5 mg / day was effective in reducing symptoms of seasonal allergic rhinitis ( hay fever ), perennial allergic rhinitis, and chronic idiopathic urticaria (chronic urticaria of unknown cause , which improves the quality of treatment). life, with an acceptable tolerance profile) .
Get the word of drug information
The advantage of second-generation antihistamines (Zyrtec and Ksizal) is the absence of unwanted side effects such as sedation, drowsiness, and difficulty concentrating and learning. These side effects are of particular concern when school-age children are treated with hydroxyzine for long periods.
Studies have shown that xizal (levocetirizine) is the only antihistamine that does not have clinically significant side effects on the physical and psychomotor development of children aged six months to 12 years.
However, hydroxyzine is still not allergic to treat mild anxiety, insomnia, nausea, and vomiting. It can also be an inexpensive short-term medication for allergic adults where sedation side effects can be helpful (such as insomnia or anxiety).