Disclaimer: None of the information in this article constitutes medical advice, and is just the opinion of the writer(s). We recommend that patients follow their doctor’s guidance in regards to prescription medication.
Hydroxyzine is a prescription antihistamine medication which is approved for the treatment of anxiety by the Food and Drug Administration (FDA). Its mechanism of action is somewhat unique, as most of the anxiety medications we’ve previously reviewed like Lexapro belong to a class of drugs called Selective Serotonin Reuptake Inhibitor (SSRI).
In this article we’ll review the medical research on hydroxyzine to determine if it’s likely to be effective for anxiety, as well as explain how it works. We’ll also highlight a natural anxiety alternative available over-the-counter (OTC) that patients may want to talk to their doctor about.
Hydroxyzine For Anxiety Review
For a medication to be approved by the FDA, it must demonstrate significant clinical data backing its efficacy. Hydroxyzine is no exception.
A clinical trial of hydroxyzine for anxiety found that at a daily dose of 50 milligrams (mg), it was more effective than placebo to a statistically significant degree, both after 1 week and after 4 weeks. This study was published in 1994, proving how long hydroxyzine has been used to treat anxiety.
A more recent medical review published in the Evidence-Based Practice journal evaluated five different trials on hydroxyzine for anxiety. The researchers found that hydroxyzine was more effective for Generalized Anxiety Disorder than placebo, and was similarly effective to other first-line treatments such as benzodiazepines.
It’s important to note that most of the medical research proving hydroxyzine’s effectiveness is on patients with Generalized Panic Disorder, which is one of the less severe forms of anxiety based on medical classification.
We only located one clinical study evaluating hydroxyzine for panic disorder. It was a case report, meaning the study documented the positive effect of the treatment on one patient. While this is useful information, we don’t believe it’s enough data to suggest that hydroxyzine is effective for panic disorder overall.
We can conclude from the above-linked research that hydroxyzine is effective for anxiety in most patients.
Hydroxyzine Side Effects
Like most pharmaceutical medication, hydroxyzine carries a risk of side effects that patients and their doctors have to balance against the benefits.
The previously-linked study from 1994 compared the side effects of hydroxyzine against placebo. Overall side effects were reported in 52% of hydroxyzine patients versus 35% of placebo.
Sleepiness was 14% more common in the hydroxyzine group, weight gain was 2% more common and dry mouth was 9% more common.
The benefit of hydroxyzine compared with many common classes of anxiety medications like SSRI is the side effect profile seems relatively mild. The FDA label even notes that side effects reported with use of hydroxyzine are “usually mild and transitory in nature.”
Hydroxyzine carries no “black box” label warning, which is a warning required by the FDA to be included on labels of medications with serious side effect risk, and is quite common in anxiety medications. Our Zoloft reviews article highlighted how that medication, which is often prescribed for anxiety and panic disorders, carries a black box warning indicating it can increase suicide risk.
Overall it appears that hydroxyzine’s side effect profile is much less concerning in comparison with other popular anxiolytic (anti-anxiety) medications.
How Does Hydroxyzine Work?
It’s important for patients to understand how their medications work.
While researchers haven’t entirely understood why hydroxyzine is effective for anxiety, it’s been suggested that it’s an antagonist at receptors in the brain that influence serotonin metabolism.
Serotonin is a neurotransmitter that influences mood and sedation, so patients with anxiety disorders often have irregular metabolism of this compound, and hydroxyzine seems to normalize this process somewhat.
The above-linked medical review suggests that hydroxyzine’s anti-anxiety activity is caused by its “suppression of certain subcortical regions”. This suggests that overactivity in these regions is the cause of the patient’s anxiety.
Generic Vs. Brand Name Version
Hydroxyzine is the name of the generic drug, and the branded version is called Vistaril.
These two names refer to the exact same chemical compound; trademarking and branding is just a business and marketing decision.
We typically recommend patients take the generic version of a drug because it’s typically cheaper. An extensive medical review published in the PLOS Medicine journal compared the effectiveness of generic versus brand-name drugs, and concluded that generic drugs provided the same level of efficacy.
This result is unsurprising given that generic and brand-name drugs are the same compound, but it was useful to see it reported in clinical research.
Hydroxyzine For Sleep
Many antihistamines, hydroxyzine included, have increased drowsiness as a side effect as we reported in the section on side effects of this drug. Taking hydroxyzine to improve sleep is an off-label use of the drug and not one we recommend.
While there are a few case reports and studies of hydroxyzine for insomnia in very specific circumstances, there doesn’t appear to be any research proving it’s effective for healthy patients with insomnia.
A review of pharmacotherapy for insomnia reported in regards to hydroxyzine for sleep that “there are few data to support its efficacy or safety for this indication.”
We tend to recommend melatonin as a first-line treatment for sleep, because it’s extremely safe and non-toxic as we highlighted in our is melatonin safe article. Patients with more extreme sleep conditions may necessitate a prescription sleep medication, but patients with more minor sleep conditions should speak with their doctor about melatonin.
Natural Alternative for Anxiety
In most of our articles we like to highlight a more natural alternative to pharmaceutical medication for the health condition, that patients may wish to speak to their doctor about.
In some cases, if the health condition is less severe, it makes sense to trial a natural product first such as a vitamin or supplement which may have lower risk of side effects than pharmaceutical medication.
Ashwagandha is a plant that’s often prepared into a root extract to treat anxiety, and this supplement has been shown in numerous medical studies to be effective as an anxiolytic.
A recent clinical trial published in the Medicine journal evaluated the stress-relieving effect of ashwagandha extract at a dosage of 240 mg. The study is placebo-controlled and double-blind which is the gold standard in medical research for objective and unbiased data.
The study authors found that ashwagandha supplementation reduced anxiety to a statistically significant degree, caused reductions in morning cortisol levels (which is a stress hormone that gets dysregulated in anxiety disorder), and even increased testosterone in males.
An extensive meta-review of herbal treatments for psychological disorders concluded the same: that ashwagandha reduced stress and cortisol in anxious patients.
When choosing an herbal supplement, we recommend only purchasing from companies that publish independent test results proving their products are accurately labeled and have safe levels of contaminants like heavy metals. The supplement industry is much less standardized and regulated than the pharmaceutical industry, so it’s important to vet any suppliers thoroughly. If a company won’t provide test results proving their products are safe, we recommend avoiding them.