Vistaril 100mg 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
First-generation antihistamine; Piperazine derivative; H1-receptor antagonist
Pregnancy Category
C
FDA Approved
Mar 1956
DEA Schedule
Not Controlled
Overview
What is this medicine?
Hydroxyzine is an antihistamine that can help reduce anxiety and tension, and relieve itching from allergies. It works by affecting certain natural substances in the brain and body.
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, take it with food to help minimize this side effect.
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 drawer, and avoid storing it in the bathroom. Ensure that all medications are kept 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 by your pharmacist. 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 on a regular schedule, take a missed dose as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your normal dosing schedule. Do not take two doses at the same time or take extra doses. If you take this medication as needed, do not take it more frequently than directed by your doctor.
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, take it with food to help minimize this side effect.
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 drawer, and avoid storing it in the bathroom. Ensure that all medications are kept 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 by your pharmacist. 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 on a regular schedule, take a missed dose as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your normal dosing schedule. Do not take two doses at the same time or take extra doses. If you take this medication as needed, do not take it more frequently than directed by your doctor.
Lifestyle & Tips
- Avoid alcohol and other medications that cause drowsiness, as hydroxyzine can increase these effects.
- Do not drive or operate heavy machinery until you know how this medication affects you, as it can cause significant drowsiness and dizziness.
- To relieve dry mouth, suck on sugarless candy or ice chips, or use a saliva substitute.
- Stay hydrated to help with potential constipation and dry mouth.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
Varies by indication
Dose Range:
25 - 400 mg
Condition-Specific Dosing:
Anxiety and Tension:
50-100 mg orally, 4 times daily
Pruritus (due to allergic conditions):
25 mg orally, 3 to 4 times daily
Preoperative Sedation:
50-100 mg orally, single dose
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established (generally not recommended for infants <6 months)
Child:
Pruritus: 0.6 mg/kg/day (or 50 mg/m2/day) in divided doses; Preoperative Sedation: 0.6 mg/kg (or 50 mg/m2) single dose
Adolescent:
Dosing similar to adult for pruritus (25 mg TID/QID) or anxiety (25-50 mg TID/QID), adjust based on response and tolerability.
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment recommended, but monitor for increased sedation.
Moderate:
Consider dose reduction by 50% or extend dosing interval.
Severe:
Consider dose reduction by 50% or extend dosing interval. Avoid if possible.
Dialysis:
Hydroxyzine is not significantly removed by dialysis. Administer after dialysis. Consider dose reduction.
Hepatic Impairment:
Mild:
Consider dose reduction by 33% to 50%.
Moderate:
Consider dose reduction by 33% to 50%.
Severe:
Consider dose reduction by 50% or more. Avoid if possible.
Pharmacology
Mechanism of Action
Hydroxyzine is a first-generation antihistamine that acts as a potent H1-receptor antagonist. Its anxiolytic and sedative effects are attributed to its activity on subcortical areas of the central nervous system, including the limbic system and reticular formation. It also possesses anticholinergic, antiemetic, antispasmodic, and local anesthetic properties.
Pharmacokinetics
Absorption:
Bioavailability:
High (well-absorbed)
Tmax:
2-4 hours
FoodEffect:
Food may delay Tmax but does not significantly affect extent of absorption.
Distribution:
Vd:
Approximately 16 L/kg
ProteinBinding:
Approximately 93%
CnssPenetration:
Yes (readily crosses the blood-brain barrier)
Elimination:
HalfLife:
Adults: 20-25 hours (can be prolonged in elderly, renal, or hepatic impairment); Children: 7-11 hours
Clearance:
Not available (highly variable)
ExcretionRoute:
Primarily renal (as metabolites, with cetirizine being the major urinary metabolite)
Unchanged:
<1% (of parent drug)
Pharmacodynamics
OnsetOfAction:
15-30 minutes
PeakEffect:
2-4 hours
DurationOfAction:
4-6 hours (sedation), up to 24 hours (antihistaminic effects)
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While 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 immediate medical attention:
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
Abnormal heartbeat or fast heart rate
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 persist, contact your doctor:
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.
While 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 immediate medical attention:
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
Abnormal heartbeat or fast heart rate
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 persist, contact your doctor:
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
- Difficulty urinating
- Blurred vision or eye pain
- Fast, pounding, or irregular heartbeat (palpitations)
- Confusion or hallucinations
- Unusual muscle movements or tremors
- Skin rash, hives, or severe itching (signs of allergic reaction)
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. Note that this medication should not be taken during early pregnancy.
If you are breastfeeding. You should not breastfeed while taking this medication.
This list is not exhaustive, and it is crucial 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 issues. Never start, stop, or adjust 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. Note that this medication should not be taken during early pregnancy.
If you are breastfeeding. You should not breastfeed while taking this medication.
This list is not exhaustive, and it is crucial 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 issues. Never start, stop, or adjust 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 engaging in activities that require alertness, such as driving, wait until you understand how this drug affects you. Consult your doctor before consuming alcohol, using marijuana or other cannabis products, or taking prescription or over-the-counter medications that may impair your reactions.
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. Discuss this risk with your doctor.
If you are 65 years or older, exercise caution when using this medication, as you may be more susceptible to side effects. If you are pregnant or planning to become pregnant, consult your doctor to weigh the benefits and risks of using this medication during pregnancy.
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. Discuss this risk with your doctor.
If you are 65 years or older, exercise caution when using this medication, as you may be more susceptible to side effects. If you are pregnant or planning to become pregnant, consult your doctor to weigh the benefits and risks of using this medication during pregnancy.
Overdose Information
Overdose Symptoms:
- Severe sedation or coma
- Confusion
- Hallucinations
- Seizures
- Severe dry mouth
- Blurred vision
- Urinary retention
- Constipation
- Hypotension (low blood pressure)
- Tachycardia (fast heart rate)
- QT prolongation, Torsade 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, including gastric lavage, activated charcoal, and maintaining vital signs. There is no specific antidote.
Drug Interactions
Contraindicated Interactions
- QT-prolonging drugs (e.g., Class IA and III antiarrhythmics, some antipsychotics, macrolide antibiotics, fluoroquinolone antibiotics, certain antifungals, methadone, citalopram, etc.) due to risk of Torsade de Pointes.
- Other CNS depressants (e.g., alcohol, opioids, benzodiazepines, barbiturates, sedating antihistamines) due to additive CNS depression.
Major Interactions
- Anticholinergic drugs (e.g., tricyclic antidepressants, atropine, benztropine) due to additive anticholinergic effects (dry mouth, urinary retention, constipation, blurred vision).
- Monoamine Oxidase Inhibitors (MAOIs) due to potential for increased CNS depression and anticholinergic effects.
- Beta-blockers (e.g., metoprolol, propranolol) - some sources suggest potential for increased hydroxyzine levels, though clinical significance is often minor.
Moderate Interactions
- Drugs metabolized by CYP3A4/5 (e.g., some statins, calcium channel blockers) - minor interaction, clinical significance generally low.
- Antihypertensives (may cause additive hypotensive effects).
Minor Interactions
- Not available
Monitoring
Baseline Monitoring
ECG (Electrocardiogram)
Rationale: To assess baseline QT interval, especially in patients with pre-existing cardiac conditions, electrolyte imbalances, or those on other QT-prolonging medications.
Timing: Prior to initiation in at-risk patients.
Renal and Hepatic Function Tests
Rationale: To guide dose adjustments in patients with impaired organ function, as hydroxyzine is metabolized by the liver and excreted by the kidneys.
Timing: Prior to initiation in patients with suspected or known impairment.
Routine Monitoring
Sedation Level
Frequency: Daily, or as needed
Target: Desired level of sedation without excessive drowsiness or impairment.
Action Threshold: Excessive sedation, somnolence, or impaired cognitive function warrants dose reduction or discontinuation.
Anticholinergic Effects (e.g., dry mouth, blurred vision, urinary retention, constipation)
Frequency: Daily, or as needed
Target: Minimal to no anticholinergic symptoms.
Action Threshold: Significant or bothersome anticholinergic symptoms warrant dose reduction or discontinuation.
Symptom Relief (e.g., anxiety, pruritus)
Frequency: Daily, or as needed
Target: Improvement in target symptoms.
Action Threshold: Lack of efficacy after adequate trial warrants re-evaluation of therapy.
Symptom Monitoring
- Drowsiness
- Dizziness
- Dry mouth
- Blurred vision
- Urinary retention
- Constipation
- Confusion (especially in elderly)
- Tremor
- Headache
- QT prolongation symptoms (palpitations, syncope, seizures - rare but serious)
Special Patient Groups
Pregnancy
Category C. Use only if the potential benefit justifies the potential risk to the fetus. Avoid during early pregnancy, especially the first trimester, due to potential for fetal abnormalities observed in animal studies at high doses. Avoid use during labor and delivery due to potential for CNS depression in the neonate.
Trimester-Specific Risks:
First Trimester:
Potential for fetal abnormalities (animal studies). Generally avoided.
Second Trimester:
Limited human data. Use with caution if clearly needed.
Third Trimester:
Potential for neonatal CNS depression, hypotonia, and anticholinergic effects if used close to delivery.
Lactation
L3 (Moderately Safe). Hydroxyzine and its active metabolite, cetirizine, are excreted into breast milk. Potential for infant sedation, irritability, and anticholinergic effects (e.g., dry mouth, urinary retention). Use with caution; monitor infant for adverse effects. Consider alternative if possible, especially in preterm or jaundiced infants.
Infant Risk:
Sedation, irritability, anticholinergic effects (e.g., dry mouth, urinary retention), potential for paradoxical excitation.
Pediatric Use
Dosing is weight-based. Children may experience paradoxical excitation (restlessness, agitation) instead of sedation. Use with caution in children under 6 months due to limited data and potential for increased sensitivity to adverse effects.
Geriatric Use
Elderly patients are more susceptible to the sedative and anticholinergic effects (e.g., confusion, urinary retention, constipation, falls). Start with lower doses (e.g., 25 mg daily or BID) and titrate slowly. Avoid if possible in patients with dementia or high risk of falls. The Beers Criteria recommend avoiding hydroxyzine in older adults due to its strong anticholinergic properties and risk of sedation.
Clinical Information
Clinical Pearls
- Hydroxyzine is effective for acute anxiety and pruritus, but its sedative and anticholinergic side effects limit its long-term use, especially in the elderly.
- Due to its QT-prolonging potential, it should be used with caution or avoided in patients with pre-existing cardiac conditions, electrolyte imbalances, or those on other QT-prolonging medications.
- The active metabolite, cetirizine (Zyrtec), is less sedating and has fewer anticholinergic effects, making it a preferred choice for chronic allergic conditions.
- Patients should be warned about the potential for significant drowsiness and advised to avoid driving or operating machinery.
- Consider alternative therapies for chronic anxiety (e.g., SSRIs, SNRIs) or chronic pruritus (e.g., topical corticosteroids, other antihistamines with better safety profiles).
Alternative Therapies
- For anxiety: Benzodiazepines (e.g., lorazepam, alprazolam - for short-term use), Buspirone (for chronic anxiety), SSRIs/SNRIs (for chronic anxiety disorders).
- For pruritus: Other antihistamines (e.g., cetirizine, loratadine, fexofenadine - less sedating; diphenhydramine - similar sedation), topical corticosteroids, doxepin (topical or oral for severe pruritus).
- For sedation/insomnia: Diphenhydramine, zolpidem, trazodone (off-label).
Cost & Coverage
Average Cost:
$10 - $50 (generic); $100 - $300+ (brand) per 30 capsules (100mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (for generic hydroxyzine); Tier 3 or higher (for brand Vistaril)
General Drug Facts
If your symptoms or health issues persist or worsen, it is 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 it is a good idea to consult with your pharmacist. If you have any questions or concerns about this medication, do not hesitate to discuss them with 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 detailed information about the overdose, including the medication taken, the amount, and the time it occurred.