One common medication often used to treat general anxiety disorder is hydroxyzine (often known by the brand names Atarax or Vistaril). On this page, we’ve outlined some important information about this prescription.

What is hydroxyzine?

What is hydroxyzine? How does it work?

Hydroxyzine is a medication used to treat anxiety disorders, usually as an adjunctive or secondary medication. It may also be used to treat allergies, hives, and contact or atopic dematoses. The medication can also be used to induce sleep before surgery. It is available by prescription only.

Hydroxyzine belongs to a class of medications called anti-histamines. Histamine is a compound found throughout the body and plays a role in keeping someone awake as well as in bodily inflammation. The medicine, hydroxyzine, works by decreasing histamine activity which can help cause sleep and reduce inflammation. Hydroxyzine also can increase serotonin activity and serotonin is an important natural brain chemical responsible for feelings of well-being and happiness.

How is hydroxyzine typically used?

For anxiety, the typical adult dose for hydroxyzine is 50-100 mg orally, up to 4 times a day. Children can take 6.25-100 mg orally per day, depending on their age. Dosage amounts can differ from person to person depending on what is being treated and the severity of the condition. 

Talk to your doctor if you feel ready to stop taking hydroxyzine. Your doctor might advise you to taper off the drug gradually (decreasing your dosage in increments over a period of time) in order to avoid any negative reactions associated with coming off of the drug too quickly. How long this takes usually depends on the patient. 

What are some possible side effects?

Some common side effects of hydroxyzine include:

• Sedation
• Dry mouth
• Fatigue
• Dizziness
• Confusion (common in older adults)
• Constipation (especially in older adults)
• Headache

Some serious (but uncommon side effects) include:

• Unintentional trembling 
• Seizures
• Muscle spasms
• Urinary retention
• Hallucinations

Call 911 or seek emergency care if you notice any severe side effects. See a more comprehensive list of hydroxyzine side effects here. 

Why do these side effects occur? 

Any medication can potentially lead to side effects, and a person’s likelihood of having side effects depends on many factors, including age, lifestyle, and the type of medication itself. Side effects may occur because drugs often have broad or poorly targeted effects, or the drug target itself may have many downstream effects on the body.

For example, hydroxyzine blocks the release of the histamine chemical in the body to help control allergic reactions. However, this chemical also helps with several other processes in the body e.g. muscle contraction, digestion, blood pressure, etc. Some of these other processes are affected when histamine is blocked. This is the major cause of most of the side effects associated with hydroxyzine.   

Many non-serious side effects of mental health medications like hydroxyzine go away after a few weeks as your body gets used to the medication. However, if a side effect persists, is intolerable, or severely hinders your ability to go about your daily life, talk to your doctor, because this might be a sign that the medication is not a good fit. 

How do your genes relate to hydroxyzine? 

Genetics can affect your body’s response to medication. Some people with a certain variation of the genes CYP3A4 and CYP3A5 might be slow metabolizers for hydroxyzine. Being a slow metabolizer means your body will break down the medication more slowly than others, which means the drug sticks around in your body for longer than average and may lead to side effects. For slow metabolizers, a doctor might opt to prescribe a different medication or prescribe a lower dosage. 

One way to predict whether you’ll have a positive outcome while taking hydroxyzine is by taking a genetic test to determine what genetic variations you have and how they affect medication metabolization. Your DNA can help your doctor rule out less suitable medications and make more informed decisions so that you can get better, faster.

Special Precautions

• Inform your doctor of any other medication or supplements you are taking before taking them alongside hydroxyzine as taking some medications alongside hydroxyzine can cause severe complications. 
• Notify your doctor if you have a medical or family history of any heart illness before taking hydroxyzine. 
• Alcohol can worsen the side effects of hydroxyzine. Avoid taking alcohol when using hydroxyzine, or talk with your doctor about the safe use of alcohol while on the medication. 
• Hydroxyzine can make you drowsy. Avoid driving or handling heavy machinery after using the medication.
• Older patients should talk with their doctor to confirm that the benefits of hydroxyzine outweighs its risks before they start taking the medication.
• Pregnant and breastfeeding mothers should talk with their doctors to confirm that the benefits of taking hydroxyzine outweighs the risks associated with the medication. 

If you show signs of an allergic reaction to hydroxyzine (hives, difficulty breathing, rash, swelling), call 911 or go to the nearest emergency department.

Some medications, vitamins, and herbs may interfere with how hydroxyzine works. Make sure to tell your doctor about all other medications you are taking before starting hydroxyzine to avoid negative interactions. For full details, see the FDA’s full list of precautions. 

Looking to find the right medication for your mental health? Join Prairie today to connect to expert providers and affordable medication options.