Hydroxyzine is an antihistamine that works by blocking the action of histamine, a substance in the body that triggers allergy symptoms [1]. It is used to treat symptoms of allergic reactions, such as itching, hives, and rash [1]. Beyond its antihistamine properties, hydroxyzine also has sedative, anti-anxiety, and antiemetic (anti-vomiting) effects [2].
What conditions does hydroxyzine treat?
Hydroxyzine is prescribed for the symptomatic relief of pruritus (itching) due to allergic conditions such as chronic urticaria (hives) and atopic dermatitis [3]. It is also used to manage anxiety and tension associated with psychoneurotic conditions [3]. Additionally, hydroxyzine can be used as a premedication for patients undergoing general anesthesia, to relieve nausea and vomiting, and to control histamine release during surgery [3].
How quickly does hydroxyzine start working and how long do its effects last?
The onset of action for hydroxyzine can vary. Its sedative effects typically begin within 15 to 45 minutes after administration [4]. For allergic symptoms, relief may be noticeable within a similar timeframe [4]. The sedative effects can last for several hours [4].
What are the common side effects of hydroxyzine?
The most frequently reported side effects of hydroxyzine include drowsiness and dry mouth [5]. Other common side effects can be dizziness, blurred vision, and constipation [5]. Less common side effects may include confusion, headaches, and coordination problems [5].
Are there any serious risks or precautions associated with hydroxyzine use?
Hydroxyzine can cause significant drowsiness, which may impair a person's ability to drive or operate heavy machinery [4]. Patients should avoid alcohol while taking hydroxyzine, as it can intensify drowsiness [4]. Caution is also advised in individuals with certain medical conditions, such as glaucoma, enlarged prostate, or respiratory difficulties, as hydroxyzine may worsen these issues [5]. There is a potential for QT interval prolongation with hydroxyzine, which can lead to serious heart rhythm problems, particularly at higher doses or in patients with risk factors [6].
Can hydroxyzine be used for anxiety?
Yes, hydroxyzine is indicated for the management of anxiety and tension associated with psychoneurotic conditions [3]. Its tranquilizing effect can help alleviate feelings of nervousness and restlessness [2].
How does hydroxyzine compare to other antihistamines?
Hydroxyzine is a first-generation antihistamine. Unlike newer, second-generation antihistamines, it readily crosses the blood-brain barrier, which accounts for its significant sedative and anti-anxiety properties [2]. Second-generation antihistamines, such as loratadine or cetirizine, are generally preferred for allergy symptom relief when sedation is undesirable because they cause less drowsiness [7].
What is the typical dosage of hydroxyzine?
Dosage for hydroxyzine is determined by the condition being treated and the patient's age and response. For adults with allergic conditions, the usual dose is 25 mg four times a day, with a maximum of 100 mg per day [3]. For anxiety, doses typically range from 25-100 mg per day [3]. It is important to follow a healthcare provider's specific instructions regarding dosage [3].
Are there alternatives to hydroxyzine for allergy symptoms or anxiety?
For allergy symptoms, numerous non-sedating second-generation antihistamines are available, such as cetirizine, loratadine, and fexofenadine [7]. For anxiety, other classes of medications like selective serotonin reuptake inhibitors (SSRIs) or benzodiazepines may be prescribed, depending on the severity and type of anxiety [8]. Behavioral therapies are also a common alternative or adjunct treatment for anxiety [8].
Who manufactures hydroxyzine?
Hydroxyzine is available as a generic medication, meaning it is manufactured by multiple pharmaceutical companies.
What is the patent status of hydroxyzine?
As hydroxyzine is an older medication, its primary patents have long expired. Information on any remaining patents or exclusivity related to specific formulations or indications can be found on resources like DrugPatentWatch.com [9].
Sources:
1. https://www.nhs.uk/medicines/hydroxyzine/
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4186117/
3. https://medlineplus.gov/druginfo/meds/a681000.html
4. https://www.ncbi.nlm.nih.gov/books/NBK557816/
5. https://www.drugs.com/sfx/hydroxyzine-side-effects.html
6. https://www.rxlist.com/consumer/hydroxyzine
7. https://www.mayoclinic.org/diseases-conditions/hay-fever/in-depth/allergy-medications/art-20047232
8. https://www.mayoclinic.org/diseases-conditions/anxiety/diagnosis-treatment/drc-20350967
9. https://drugpatentwatch.com/