What are the long-term effects of Hydroxyzine (Atarax, antihistamine)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: February 21, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Hydroxyzine should be used with caution for long-term treatment due to its potential for sedation, performance impairment, and anticholinergic effects, which can significantly impact morbidity, mortality, and quality of life. The long-term effects of hydroxyzine may include:

  • Drowsiness and sedation, which can lead to impaired driving performance and increased risk of accidents, as reported in a study where drivers responsible for fatal automobile accidents were 1.5 times more likely to be taking first-generation antihistamines like hydroxyzine 1
  • Dry mouth, constipation, and other anticholinergic effects, which can be undesirable and potentially dangerous, especially in older adults who are more sensitive to these effects 1
  • Potential cognitive impairment in older adults, which can increase the risk of falls, fractures, and subdural hematomas, making it essential to approach the use of hydroxyzine with caution in this population 1
  • Impaired learning and school performance in children, as well as driving impairment in adults, highlighting the need for careful consideration of the potential risks and benefits of hydroxyzine treatment 1

For long-term use, it is crucial to use the lowest effective dose, especially in elderly patients, and to monitor patients regularly to assess ongoing effectiveness and potential side effects. Patients should be aware that tolerance to the sedative effects may develop over time, and regular follow-ups with a healthcare provider are essential to minimize the risks associated with hydroxyzine treatment. Additionally, patients should avoid alcohol and other central nervous system depressants while taking hydroxyzine to reduce the risk of adverse interactions. Overall, the potential risks and benefits of hydroxyzine treatment should be carefully weighed, and alternative treatments with a lower likelihood of adverse effects should be considered, especially for long-term use 1.

From the FDA Drug Label

The effectiveness of hydroxyzine as an antianxiety agent for long term use, that is more than 4 months, has not been assessed by systematic clinical studies. The long-term effects of Hydroxyzine are not established for use beyond 4 months, as there are no systematic clinical studies that assess its effectiveness for long-term use 2.

  • The physician should reassess periodically the usefulness of the drug for the individual patient.
  • No conclusion can be drawn about the long-term effects of Hydroxyzine due to the lack of direct evidence.

From the Research

Long-term Effects of Hydroxyzine

The long-term effects of hydroxyzine, an antihistamine medication, have been studied in various contexts. Some key findings include:

  • Hydroxyzine has been found to be effective in treating generalized anxiety disorder (GAD) in the short-term, with some studies suggesting its efficacy over a 3-month period 3.
  • However, the long-term use of hydroxyzine in children under the age of 5 has been associated with an increased risk of mental and psychomotor disorders, such as tics, anxiety, and disturbance of conduct 4.
  • In terms of safety, hydroxyzine has been found to have a similar side effect profile to other anxiolytic agents, with the exception of a higher rate of sleepiness/drowsiness 5.
  • Bedtime dosing of hydroxyzine has been shown to mitigate some of the objective antihistamine side effects, such as reaction time degradation and adverse subjective symptoms 6.

Neurodevelopmental Effects

The neurodevelopmental effects of hydroxyzine have been studied in a population-based longitudinal study, which found that:

  • Frequent use of hydroxyzine in children under the age of 5 was associated with an increased risk of tic disorder, anxiety, and disturbance of conduct up to the age of 10 years 4.
  • The study suggested that controlled studies are required to prove a causal relationship and to confirm the safety of hydroxyzine in the pediatric population.

Comparison to Other Medications

Hydroxyzine has been compared to other medications, such as benzodiazepines and buspirone, in terms of efficacy and safety. Some key findings include:

  • Hydroxyzine was found to be equivalent to other anxiolytic agents in terms of efficacy, acceptability, and tolerability 5.
  • Hydroxyzine was found to have a lower rate of antimuscarinic findings compared to diphenhydramine, another antihistamine medication 7.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.