Vistaril 25mg Capsules
It is used to treat itching.It is used to treat anxiety.It is used to put you to sleep for surgery.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Antihistamine, Anxiolytic, Sedative-Hypnotic
Pharmacologic Class
H1-receptor antagonist
Pregnancy Category
Category C
FDA Approved
Mar 1956
DEA Schedule
Not Controlled
Overview
What is this medicine?
Hydroxyzine is an antihistamine that can help reduce anxiety, relieve itching from allergies, and cause drowsiness to help with sleep before surgery. It works by blocking a natural substance (histamine) in your body and by affecting certain areas of the brain to calm you.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. You can take this medication with or without food. If it causes stomach upset, taking it with food may help.
Storing and Disposing of Your Medication
Store this medication at room temperature, away from light and moisture. Keep it in a dry place, such as a closet or cupboard, and avoid storing it in the bathroom. Keep all medications in a safe location, out of the reach of children and pets. When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so. Instead, check with your pharmacist for guidance on the best disposal method or participate in a local drug take-back program if available.
Missing a Dose
If you take this medication regularly and miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your regular schedule. Do not take two doses at the same time or take extra doses. If you take this medication as needed, follow your doctor's instructions and do not take it more frequently than recommended.
To use this medication correctly, follow your doctor's instructions and read all the information provided. You can take this medication with or without food. If it causes stomach upset, taking it with food may help.
Storing and Disposing of Your Medication
Store this medication at room temperature, away from light and moisture. Keep it in a dry place, such as a closet or cupboard, and avoid storing it in the bathroom. Keep all medications in a safe location, out of the reach of children and pets. When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so. Instead, check with your pharmacist for guidance on the best disposal method or participate in a local drug take-back program if available.
Missing a Dose
If you take this medication regularly and miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your regular schedule. Do not take two doses at the same time or take extra doses. If you take this medication as needed, follow your doctor's instructions and do not take it more frequently than recommended.
Lifestyle & Tips
- Avoid alcohol and other sedating medications (e.g., opioids, benzodiazepines) while taking hydroxyzine, as this can increase drowsiness and dizziness.
- Do not drive or operate heavy machinery until you know how this medication affects you, as it can cause significant drowsiness and impair your ability to perform tasks requiring alertness.
- Avoid activities that require mental alertness until you are aware of the drug's effects.
- Stay hydrated to help manage dry mouth, a common side effect.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
Anxiety: 50-100 mg four times daily (Hydroxyzine HCl) or 25-100 mg three to four times daily (Hydroxyzine Pamoate). Pruritus: 25 mg three to four times daily. Pre-operative sedation: 50-100 mg single dose.
Dose Range:
25 - 400 mg
Condition-Specific Dosing:
anxiety:
50-100 mg QID (HCl); 25-100 mg TID/QID (Pamoate)
pruritus:
25 mg TID/QID
preoperative_sedation:
50-100 mg single dose
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established for routine use; consult specialist for specific indications.
Child:
Pruritus/Anxiety: 0.6 mg/kg/day in divided doses (Hydroxyzine HCl); 0.5-1 mg/kg/day in divided doses (Hydroxyzine Pamoate). Pre-operative sedation: 0.6 mg/kg single dose. Max 100 mg/day.
Adolescent:
Pruritus/Anxiety: 0.6 mg/kg/day in divided doses (Hydroxyzine HCl); 0.5-1 mg/kg/day in divided doses (Hydroxyzine Pamoate). Pre-operative sedation: 0.6 mg/kg single dose. Max 100 mg/day.
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment, monitor for increased sedation.
Moderate:
Consider 50% dose reduction or extended dosing interval.
Severe:
Consider 50% dose reduction or extended dosing interval; avoid if possible due to accumulation of active metabolite (cetirizine).
Dialysis:
Not well studied; cetirizine is dialyzable, but hydroxyzine is not. Use with caution, significant dose reduction likely needed.
Hepatic Impairment:
Mild:
No specific adjustment, monitor for increased sedation.
Moderate:
Consider 50% dose reduction or extended dosing interval.
Severe:
Consider 50% dose reduction or extended dosing interval; avoid if possible.
Pharmacology
Mechanism of Action
Hydroxyzine is a piperazine derivative that acts as a potent H1-receptor antagonist, competing with histamine for receptor sites on effector cells. This antagonism leads to its antihistaminic, antipruritic, and antiemetic effects. It also possesses anticholinergic, sedative, and mild bronchodilator properties. Its anxiolytic and sedative effects are attributed to its action on subcortical areas of the central nervous system.
Pharmacokinetics
Absorption:
Bioavailability:
Not available (well absorbed)
Tmax:
2-4 hours
FoodEffect:
Food may delay absorption but does not significantly affect the extent of absorption.
Distribution:
Vd:
16 L/kg
ProteinBinding:
Approximately 93%
CnssPenetration:
Yes
Elimination:
HalfLife:
Hydroxyzine: 14-25 hours (highly variable); Cetirizine: 8-10 hours
Clearance:
Not available
ExcretionRoute:
Primarily renal (as metabolites, including cetirizine)
Unchanged:
Less than 1% (parent drug)
Pharmacodynamics
OnsetOfAction:
15-30 minutes
PeakEffect:
2-4 hours
DurationOfAction:
4-6 hours (antihistaminic/sedative effects); up to 24 hours (antipruritic effects)
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Attention Immediately
Although rare, this medication can cause severe and potentially life-threatening side effects. If you experience any of the following symptoms, contact your doctor or seek medical help right away:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Fast or abnormal heartbeat
Severe dizziness or fainting
Difficulty controlling body movements
Confusion
A rare but serious skin reaction, characterized by:
+ Fever
+ Multiple small skin spots within large areas of redness and swelling
If you develop a rash or any of these symptoms, contact your doctor immediately.
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or do not go away, contact your doctor or seek medical help:
Dry mouth
Drowsiness
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, this medication can cause severe and potentially life-threatening side effects. If you experience any of the following symptoms, contact your doctor or seek medical help right away:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Fast or abnormal heartbeat
Severe dizziness or fainting
Difficulty controlling body movements
Confusion
A rare but serious skin reaction, characterized by:
+ Fever
+ Multiple small skin spots within large areas of redness and swelling
If you develop a rash or any of these symptoms, contact your doctor immediately.
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or do not go away, contact your doctor or seek medical help:
Dry mouth
Drowsiness
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe drowsiness or dizziness that interferes with daily activities
- Confusion, disorientation, or hallucinations (especially in older adults)
- Difficulty urinating or inability to urinate
- Severe dry mouth that is bothersome
- Blurred vision or eye pain
- Fast, pounding, or irregular heartbeat (palpitations)
- Fainting or feeling like you might faint
- Unusual muscle movements or tremors
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
A history of prolonged QT interval on an electrocardiogram (ECG).
If you are in the early stages of pregnancy. It is crucial not to take this medication during early pregnancy.
If you are breastfeeding. You should not breastfeed while taking this medication.
This list is not exhaustive, and it is vital to discuss all your medications (including prescription, over-the-counter, natural products, and vitamins) and health conditions with your doctor and pharmacist. They will help determine if it is safe to take this medication with your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
A history of prolonged QT interval on an electrocardiogram (ECG).
If you are in the early stages of pregnancy. It is crucial not to take this medication during early pregnancy.
If you are breastfeeding. You should not breastfeed while taking this medication.
This list is not exhaustive, and it is vital to discuss all your medications (including prescription, over-the-counter, natural products, and vitamins) and health conditions with your doctor and pharmacist. They will help determine if it is safe to take this medication with your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
Before operating a vehicle or engaging in any activity that requires alertness, wait until you understand how this drug affects you. It is also crucial to discuss the use of alcohol, marijuana, or other forms of cannabis, as well as prescription or over-the-counter (OTC) medications that may cause drowsiness, with your doctor beforehand.
This medication has been associated with an abnormal and potentially life-threatening heartbeat, known as a prolonged QT interval on an electrocardiogram (ECG), which may increase the risk of sudden death. Therefore, it is vital to consult with your doctor about this risk.
If you are 65 years or older, exercise caution when using this drug, as you may be more susceptible to experiencing side effects.
If you are pregnant or planning to become pregnant, notify your doctor. It is necessary to have a discussion with your doctor about the potential benefits and risks of using this medication during pregnancy.
Before operating a vehicle or engaging in any activity that requires alertness, wait until you understand how this drug affects you. It is also crucial to discuss the use of alcohol, marijuana, or other forms of cannabis, as well as prescription or over-the-counter (OTC) medications that may cause drowsiness, with your doctor beforehand.
This medication has been associated with an abnormal and potentially life-threatening heartbeat, known as a prolonged QT interval on an electrocardiogram (ECG), which may increase the risk of sudden death. Therefore, it is vital to consult with your doctor about this risk.
If you are 65 years or older, exercise caution when using this drug, as you may be more susceptible to experiencing side effects.
If you are pregnant or planning to become pregnant, notify your doctor. It is necessary to have a discussion with your doctor about the potential benefits and risks of using this medication during pregnancy.
Overdose Information
Overdose Symptoms:
- Severe sedation or coma
- Confusion, disorientation, hallucinations
- Severe anticholinergic effects (e.g., severe dry mouth, dilated pupils, blurred vision, urinary retention, decreased bowel sounds)
- Seizures
- Hypotension (low blood pressure)
- Tachycardia (fast heart rate)
- QT prolongation and Torsades de Pointes (rare but serious cardiac arrhythmia)
What to Do:
Seek immediate medical attention. Call 911 or Poison Control at 1-800-222-1222. Treatment is supportive and symptomatic. Gastric lavage may be considered if ingestion is recent. Activated charcoal may be administered. Monitor vital signs, cardiac rhythm (ECG), and mental status. Physostigmine may be used for severe anticholinergic symptoms but is generally reserved for life-threatening cases due to potential for adverse effects. Do not induce vomiting.
Drug Interactions
Contraindicated Interactions
- Patients with known QT prolongation or risk factors for QT prolongation (e.g., significant cardiac disease, uncorrected hypokalemia/hypomagnesemia, family history of sudden cardiac death)
- Concomitant use with other QT-prolonging drugs (e.g., Class IA and III antiarrhythmics, some antipsychotics, macrolide antibiotics, fluoroquinolones, certain antifungals, citalopram, escitalopram, methadone, ondansetron, tricyclic antidepressants)
Major Interactions
- CNS depressants (e.g., alcohol, opioids, benzodiazepines, barbiturates, other sedating antihistamines): Increased sedation and CNS depression.
- Anticholinergic drugs (e.g., tricyclic antidepressants, atropine, benztropine): Increased anticholinergic effects (dry mouth, blurred vision, urinary retention, constipation).
- Drugs that cause hypokalemia or hypomagnesemia: Increased risk of QT prolongation.
Moderate Interactions
- CYP3A4/5 inhibitors (e.g., ketoconazole, ritonavir): May slightly increase hydroxyzine levels, but less significant due to primary metabolism by alcohol dehydrogenase.
- CYP3A4/5 inducers (e.g., rifampin, carbamazepine, phenytoin): May slightly decrease hydroxyzine levels.
Minor Interactions
- Not available
Monitoring
Baseline Monitoring
ECG
Rationale: To assess baseline QT interval, especially in patients with cardiac risk factors or on concomitant QT-prolonging medications.
Timing: Prior to initiation in at-risk patients.
Electrolytes (Potassium, Magnesium)
Rationale: To identify and correct hypokalemia or hypomagnesemia, which can increase the risk of QT prolongation.
Timing: Prior to initiation in at-risk patients.
Renal and Hepatic Function Tests
Rationale: To guide dose adjustments in patients with impaired organ function.
Timing: Prior to initiation.
Routine Monitoring
Sedation Level
Frequency: Daily or as needed, especially during dose titration.
Target: Acceptable level of sedation without excessive impairment.
Action Threshold: Excessive drowsiness, somnolence, or impaired coordination; consider dose reduction or discontinuation.
Anticholinergic Effects
Frequency: Daily or as needed.
Target: Absence of significant dry mouth, blurred vision, urinary retention, constipation.
Action Threshold: Development of bothersome or severe anticholinergic symptoms; consider dose reduction or alternative.
Cardiac Symptoms (Palpitations, Dizziness, Syncope)
Frequency: As needed, especially if patient reports symptoms.
Target: Absence of cardiac symptoms.
Action Threshold: New onset or worsening of cardiac symptoms; investigate for QT prolongation or arrhythmias, discontinue hydroxyzine.
Symptom Monitoring
- Excessive drowsiness or sedation
- Dizziness or lightheadedness
- Dry mouth
- Blurred vision
- Urinary retention
- Constipation
- Confusion or disorientation (especially in elderly)
- Paradoxical excitation (rare, especially in children)
- Palpitations or irregular heartbeat
- Fainting or syncope
Special Patient Groups
Pregnancy
Generally not recommended during pregnancy, especially in the first trimester and near term. Animal studies show adverse effects at high doses. Use only if the potential benefit justifies the potential risk to the fetus.
Trimester-Specific Risks:
First Trimester:
Potential for fetal abnormalities based on animal studies; generally avoided.
Second Trimester:
Limited human data; use with caution if clearly needed.
Third Trimester:
Potential for neonatal withdrawal symptoms (e.g., tremors, irritability) and CNS depression (e.g., hypotonia, respiratory depression) if used close to delivery.
Lactation
Use with caution or avoid. Hydroxyzine and its active metabolite, cetirizine, are excreted into breast milk. Potential for infant sedation, irritability, and anticholinergic effects. May also decrease milk supply.
Infant Risk:
Moderate to High (L3-L4). Monitor infant for sedation, poor feeding, irritability, and anticholinergic effects. Consider alternative agents with less infant exposure or lower risk.
Pediatric Use
Use with caution. Children may be more susceptible to paradoxical excitation (hyperactivity, agitation) or, more commonly, excessive sedation. Dosing is weight-based. Avoid in neonates and infants due to lack of established safety and efficacy.
Geriatric Use
Use with extreme caution. Elderly patients are more susceptible to the sedative and anticholinergic effects (e.g., confusion, urinary retention, constipation, dry mouth, blurred vision), increasing the risk of falls and cognitive impairment. Start with the lowest effective dose and titrate slowly. Included in the Beers Criteria as a medication to avoid in older adults due to high anticholinergic burden and risk of sedation/falls.
Clinical Information
Clinical Pearls
- Hydroxyzine is a first-generation antihistamine with significant sedative and anticholinergic properties. It is not recommended for long-term management of anxiety.
- Due to its potential for QT prolongation, it should be used with caution in patients with cardiac risk factors or those on other QT-prolonging medications. An ECG may be warranted before initiation in at-risk patients.
- The active metabolite, cetirizine, has a longer half-life and contributes to the overall effect and potential for accumulation, especially in renal impairment.
- Often used as a non-benzodiazepine alternative for short-term anxiety or as a sedative for pruritus or pre-operative anxiety.
- Educate patients about the risk of drowsiness and to avoid driving or operating machinery.
Alternative Therapies
- For anxiety: Buspirone, SSRIs (e.g., escitalopram, sertraline), SNRIs (e.g., venlafaxine, duloxetine), benzodiazepines (short-term, e.g., lorazepam, alprazolam).
- For pruritus: Second-generation antihistamines (e.g., loratadine, fexofenadine, cetirizine), topical corticosteroids, doxepin (topical or oral).
- For sedation/insomnia: Diphenhydramine, zolpidem, zaleplon, eszopiclone, melatonin.
Cost & Coverage
Average Cost:
Varies widely, typically $10-$50 per 30 capsules (25mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (Generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about this medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide details about the overdose, including the medication taken, the amount, and the time it occurred.