Generic name: hydroxyzine [ hye-DROX-ee-zeen ]
Brand names: ANX, Vistaril, Atarax, Vistaril IM, Hyzine, Vistaject-50, Rezine
Drug classes: Antihistamines, Miscellaneous anxiolytics, sedatives and hypnotics
What is hydroxyzine?
Hydroxyzine is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of itching, or hives on the skin. Hydroxyzine may be used to treat allergic skin reactions such as hives or contact dermatitis.
Since hydroxyzine also reduces activity in the central nervous system, it can be used as a sedative to treat anxiety and tension. It is also used together with other medications given during and after general anesthesia.
Hydroxyzine is also used to treat allergic skin reactions such as hives or contact dermatitis.
Hydroxyzine may cause birth defects. Talk to you doctor before using hydroxyzine if pregnant or breastfeeding.
Hydroxyzine can cause a serious heart problem, especially if you use certain medicines at the same time. Tell your doctor about all your current medicines and any you start or stop using.
This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.
Stop using this medicine and call your doctor at once if you have a serious side effect such as tremors, confusion, seizures, or restless muscle movements in your eyes, tongue, jaw, or neck.
Drinking alcohol can increase certain side effects of hydroxyzine.
Before taking this medicine
You should not use hydroxyzine if you are allergic to it, or if:
you have long QT syndrome;
you are allergic to cetirizine (Zyrtec) or levocetirizine (Xyzal); or
Hydroxyzine could harm the unborn baby or cause birth defects. Talk to you doctor before using hydroxyzine if pregnant.
To make sure this medicine is safe for you, tell your doctor if you have:
blockage in your digestive tract (stomach or intestines);
bladder obstruction or other urination problems;
heart disease, slow heartbeats;
personal or family history of long QT syndrome;
an electrolyte imbalance (such as high or low levels of potassium in your blood);
if you have recently had a heart attack.
It is not known whether hydroxyzine passes into breast milk or if it could harm a nursing baby. Talk to your doctor before breastfeeding while using this medicine.
Do not give this medicine to a child without medical advice.
How should I take hydroxyzine?
Take hydroxyzine exactly as prescribed by your doctor. Follow all directions on your prescription label. Your doctor may occasionally change your dose. Do not use this medicine in larger or smaller amounts or for longer than recommended.
Shake the oral suspension (liquid) well just before you measure a dose. Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.
Hydroxyzine is for short-term use only.
You should not take this medicine for longer than 4 months. Call your doctor if your anxiety symptoms do not improve, or if they get worse.
Store at room temperature away from moisture and heat.
What happens if I miss a dose?
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
Overdose symptoms may include severe drowsiness, nausea, vomiting, uncontrolled muscle movements, or seizure (convulsions).
What to avoid
This medicine may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.
Drinking alcohol with this medicine can cause side effects.
Hydroxyzine side effects
Get emergency medical help if you have signs of an allergic reaction to hydroxyzine: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
In rare cases, hydroxyzine may cause a severe skin reaction. Stop taking this medicine and call your doctor right away if you have sudden skin redness or a rash that spreads and causes white or yellow pustules, blistering, or peeling.
Stop using hydroxyzine and call your doctor at once if you have:
fast or pounding heartbeats;
headache with chest pain;
severe dizziness, fainting; or
a seizure (convulsions).
Side effects such as drowsiness and confusion may be more likely in older adults.
Common hydroxyzine side effects may include:
dry mouth; or
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
What other drugs will affect hydroxyzine?
Taking this medicine with other drugs that make you sleepy can worsen this effect. Ask your doctor before taking hydroxyzine with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.
Hydroxyzine can cause a serious heart problem, especially if you use certain medicines at the same time, including antibiotics, antidepressants, heart rhythm medicine, antipsychotic medicines, and medicines to treat cancer, malaria, HIV or AIDS. Tell your doctor about all medicines you use, and those you start or stop using during your treatment with this medicine.
Other drugs may interact with hydroxyzine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.
How long does hydroxyzine stay in your system?
Hydroxyzine will stay in your system for about 100 hours, on average, but its clinical effect may wear off before this time. Hydroxyzine has a half-life of about 20 hours. The half-life of a drug is the time it takes for the plasma (blood) concentration to be reduced by 50% from its original value. It takes about 5 half-lives for a drug to be eliminated from your body, so after about 20 hours x 5 half-lives (100 hours), most of hydroxyzine is gone from an adult’s system.
Does hydroxyzine make you sleepy?
Yes, hydroxyzine is an antihistamine that can cause drowsiness and sedation. It can be used to treat anxiety and tension due to its sedative properties. It is also used as an adjunct medicine for general anesthesia during surgery and for itching or hives. Hydroxyzine can affect your thinking or reaction time and may make it dangerous for you to drive or operate dangerous machinery. Drowsiness and confusion may be more common in older patients.
How long does it take for hydroxyzine to work?
Hydroxyzine starts to work in about 15 to 30 minutes but its drowsy effect may last for 4 to 6 hours. Hydroxyzine can reduce itching and redness due to allergy skin tests for up to 4 days. Hydroxyzine is used to relieve anxiety, itching due to allergies, and as a premedication prior to surgery. Do not drive, operate machinery, or perform tasks requiring alertness if this medicine makes you drowsy.
Hydroxyzine is intended for short-term use only (less than 4 months) when used to treat anxiety. Using hydroxyzine long-term would be considered an off-label use for the drug because there are no studies looking at the long-term effects of hydroxyzine. Some research suggests a link between long-term use of medications with anticholinergic properties, such as hydroxyzine, and dementia, particularly in older adults. Brain fog has also been reported with long-term use. Continue reading
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