Hydroxyzine is a substance used in anti-allergic drugs (antihistaminics), approved in 1956. It is also a sedative, and can also be administrated to treat infections. During an allergic reaction histamine is released into the body, and that causes sneezing, itching and other allergic symptoms. Hydroxyzine is activated after ingestion and it blocks the release of histamine thus reducing allergic symptoms. The active form of the substance is cetirizine (Zyrtec). Cetirizine causes less sleepyness than hydroxyzine.
Hydroxyzine is avaliable only by medical prescription. It comes in tablets, capsules (that have to be kept at room temperature) of various concentrations, syrups and shots. Liquid hydroxyzine shouldn’t be exposed to freezint temperatures and always should be well shaken before administrated. The injectable solution has to be kept below 30°C.
Hydroxyzine is prescribed to ease itching that appears during allergies, it alleviates anxiety, tension. It can also be used as a sedative before or after anesthesia.
The effect of this substance comes after half an hour or an hour after administration and it can last up to six hours. In treating allergies the dosage is about 25 mg, administred up to four times a day. As a sedative it is used in doses of 50-100 mg. In anxiety treatment, or tension relief it is administrated up to four times a day, in doses of 50 to 100 mg. It can be taken with or without food.
Hydroxyzine interacts with alcohol and other medicines that cause sedation, or relieve anxiety (Valium, Ativan, Klonopin, Xanax). It also interacts with a certain class of pain relief medication and derivatives (Percocet, Vicodin, Dilaudid, Norpramin) and a series of drugs that are used against hypertension (Catapres, Inderal). Hydroxyzine can accentuate the effects of medicine used to block nerve impulses (Bentyl, Urecholine, Probanthine, Elavil, Thorazine). If a person is administrated any of the latter, the hydroxyzine dose may have to be reduced.
Administration during prenancy: Some studies have shown that, if administrated during the first trimester of pregnancy, hydroxyzine can lead to congenital anomalies in the fetus. It is advised not to use hydroxyzine during this time.
Administration during nursing: There are no conclusive studies to show if hydroxyzine can reach into the breast milk. Generally antiallergic medicine, like antihistamines are not recommended during nursing as they can cause severe reactions in newborns, such as seizures.
Side reactions to hydroxyzine can occur: sedation, tiredness, sleepiness, dizziness, disturbed coordination, drying and thickening of oral and other respiratory secretions, and stomach distress, confusion, nervousness, irritability, blurred vision, double vision, tremor, loss or appetite, or nausea. This substance is to be used with caution – or completely avoided – in patients suffering from glaucoma, enlargement of the prostate, hyperthyroidism, cardiovascular disease, hypertension, and asthma.