Hydroxyzine is an antihistamine medication with many uses, including the treatment of itching due to allergic reactions and anxiety conditions. Hydroxyzine is a safe medication and is unlikely to cause a risk of addiction, abuse, or dependence. However, it should be used as prescribed to prevent adverse effects and overdose.
- Hydroxyzine is an antihistamine, available as a generic medication or as a branded medication called Vistaril.
- It can be used to treat anxiety, itching due to allergic reactions, insomnia, and for sedation before and after surgery.
- Hydroxyzine can cause adverse effects and overdose, so it should be taken as prescribed.

What is hydroxyzine?
Hydroxyzine is an antihistamine that can be used in the treatment of various symptoms and conditions due to its numerous effects. [1] Hydroxyzine is available in generic form or as a brand-name medication called Vistaril, in tablets, capsules, oral suspension, or syrup. Capsules and tablets are available in strengths of 10 mg, 25 mg, and 50 mg. [1][2]
How hydroxyzine works
Hydroxyzine works by blocking histamine action at the H1 receptor, as an H1 receptor inverse agonist. Histamine is involved in various functions, including allergic reactions and itching. As an antihistamine, hydroxyzine helps to treat allergic reactions. [3][4]
Hydroxyzine is a first-generation antihistamine that crosses the blood-brain barrier, unlike second-generation antihistamines, such as fexofenadine. Antihistamines that cross the blood-brain barrier affect the central nervous system (CNS) and are more likely to cause drowsiness and sedation. [3]
Hydroxyzine has also been shown to produce muscle relaxation, pain relief, and anti-nausea effects. [1]
Medical uses
Hydroxyzine is approved for use in the treatment of: [1]
- Anxiety and tension associated with psychoneurosis or anxiety that occurs in the context of organic disease states
- Itching (pruritus) caused by allergic reactions and contact dermatoses
- General insomnia
- As a sedative before and after general anesthesia
It can be used to treat these conditions in children and adults, although use in older adults is not recommended. [2]
Research also indicates that hydroxyzine can be used as an adjunctive medication with 5-HT3 receptor antagonists such as palonosetron to help reduce the severity of opioid withdrawal symptoms. [5]
Dosage guidelines
Recommended doses for anxiety and tension are as follows: [1][2]
- Adults: 50-100 mg four times per day
- Children over the age of 6: 50-100 mg in divided doses
- Children under the age of 6: 50 mg in divided doses
Recommended doses for itching are as follows: [1][2]
- Adults: 25 mg three or four times per day
- Children over the age of 6: 50-100 mg in divided doses
- Children under the age of 6: 50 mg in divided doses
Recommended doses for use as a pre- or post-operative sedative are as follows: [1][2]
- Adults: 50-100 mg
- Children: 0.6 mg per kg of body weight
Precautions and contraindications
Precautions and contraindications for hydroxyzine use include: [1][4]
- Children should be given lower doses than adults.
- All treatments should start at the lower end of the dosing range, titrating the dose upward to achieve the desired effect, while monitoring for side effects.
- Use in geriatric populations is not recommended, but if treatment is indicated, hydroxyzine should be commenced in very low doses, and caution and close monitoring are advised.
- Pregnant or breastfeeding mothers should not take hydroxyzine.
- Hydroxyzine is not recommended for long-term use in the treatment of anxiety.
- Hydroxyzine should not be given to people with a history of heart conditions or should be used with extreme caution if necessary, as it can cause increased risks of QT prolongation.
- People with liver or kidney impairments should take hydroxyzine with caution.
- Because hydroxyzine causes drowsiness, it is advised not to drive or use heavy machinery while taking the medication or until its effects are known.
Side effects
Hydroxyzine can cause side effects, particularly at the start of a new treatment or when the dose is increased. Typically, side effects will reduce on their own within a short time and are often mild in nature. However, if side effects persist or become concerning, a doctor should be consulted. [1]
Common side effects of hydroxyzine include: [1][4]
- Drowsiness
- Headache
- Dry mouth
- Confusion
- Constipation
- Dizziness
Side effects that should be reported to a doctor include: [1][4]
- Seizures
- Uncontrollable shaking or tremors
- Rash, blisters, or sores
- Swelling and redness
- Fever
- Hallucinations
Hydroxyzine interactions: What other drugs will affect it?
Hydroxyzine has a depressant effect on the CNS. Because of this, using other CNS depressants, such as opioids, benzodiazepines, and alcohol, with hydroxyzine can lead to oversedation and harmful effects. [2]
Addiction and dependency: Myths and facts
Hydroxyzine is not considered an addictive substance, as it has little potential for abuse and dependence. It is not a controlled substance and is safe for use in adults and children. [6] Hydroxyzine does not cause euphoric effects or a “high”, and it is unlikely to lead to tolerance and dependence. As such, it typically does not cause withdrawal symptoms when treatment is stopped. [7] However, people who misuse substances may abuse hydroxyzine because of its anxiolytic and sedative effects or to enhance the effects of other substances.
As an anxiolytic medication, hydroxyzine is safe. Alternative anxiety treatment includes benzodiazepines, which are Schedule IV controlled substances, as they have potential for abuse and addiction. In contrast to hydroxyzine, benzodiazepines are only recommended for short-term use. [8]
However, compared to other treatments for allergic reactions, some people may prefer second-generation antihistamines, as they are less likely to cause drowsiness and sedation. [3]
Hydroxyzine overdose
Taking too much hydroxyzine can result in overdose. This can result in extreme sedation, as well as other adverse effects: [1][4]
- Seizures
- Nausea and vomiting
- Impaired cognitive functioning
- Loss of consciousness
If a hydroxyzine overdose is suspected, contact a medical professional or 911 immediately.
Treatment for a hydroxyzine overdose may include stomach pumping, intravenous fluids, and careful monitoring. There is no antidote for hydroxyzine overdose, so treatment involves managing symptoms and ensuring medical stability. [1]
Tips for safe use and monitoring
Always take hydroxyzine exactly as prescribed. If you miss a dose, take it when you remember, unless it is close to the next dose time. If it is almost time for the next dose, skip the missed dose and take the next one as prescribed. Never take a double dose to make up for missed doses or take hydroxyzine in higher doses or more frequently than prescribed.
Keep medications in a safe and secure location, away from children and pets.
When to contact a healthcare provider
People taking hydroxyzine should contact a medical professional if they notice concerning side effects, such as fever, seizures, or hallucinations or if an overdose is suspected.
People who are prescribed hydroxyzine should have regular follow up visits with the prescribing clinician to monitor the effectiveness of the medication and any adverse effects that occur. Treatment can be altered if needed, such as adjusting the dose or changing to a different medication.