Hydroxyzine: Difference between revisions
Appearance
| [unchecked revision] | [checked revision] |
MDElliottMD (talk | contribs) Expand stub to full MedTemplate parameter set |
MDElliottMD (talk | contribs) parser-claude: Hydroxyzine MedTemplate refill, Top 300 stub upgrade |
||
| (7 intermediate revisions by 2 users not shown) | |||
| Line 1: | Line 1: | ||
{{MedTemplate | {{MedTemplate | ||
| generic | | generic = Hydroxyzine (hydrochloride; pamoate salt) | ||
| brand | | brand = Vistaril (pamoate), Atarax (HCl, discontinued in US as brand) | ||
| structure | | structure = | ||
| classes | | classes = [[:Category:Antihistamines|First-generation antihistamine]], [[:Category:Anxiolytics|Anxiolytic]], [[:Category:Antipruritics|Antipruritic]], [[:Category:Sleep aids|Sleep aid (off-label)]] | ||
| | | uses = <vote slug="anxiety-short-term-use">Anxiety symptoms (FDA, short-term)</vote>, <vote slug="pruritus-allergic-use">Pruritus from allergic conditions (FDA)</vote>, <vote slug="preoperative-sedation-use">Preoperative sedation (FDA)</vote>, <vote slug="nausea-vomiting-im-use">Nausea and vomiting (FDA, IM only)</vote>, <vote slug="insomnia-hydroxyzine-use">Insomnia (off-label)</vote>, <vote slug="alcohol-withdrawal-adjunct-use">Acute alcohol withdrawal adjunct (off-label)</vote>, <vote slug="pediatric-agitation-use">Pediatric acute agitation (off-label)</vote> | ||
| uses | | starting_dose = Anxiety: 25-50 mg PO QID. Pruritus: 25 mg PO TID-QID. Insomnia: 25-50 mg PO at bedtime. Pediatric: 50-100 mg/day divided | ||
| preparations = Tablets 10, 25, 50 mg (HCl); capsules 25, 50, 100 mg (pamoate); oral suspension 25 mg/5 mL; injection 25, 50 mg/mL (IM only, never IV) | |||
| fda_max = 400 mg/day theoretical; in practice rarely exceeds 200 mg/day | |||
| pill_id = | |||
| routes = Oral, intramuscular | |||
| onset = 15-30 minutes (oral) | |||
| duration = 4-6 hours | |||
| halflife = 14-25 hours (longer in elderly and hepatic impairment)<ref name="vistaril-label">FDA Prescribing Information, Vistaril (hydroxyzine pamoate), Pfizer, current revision. https://www.accessdata.fda.gov/drugsatfda_docs/label/2009/011459s045lbl.pdf</ref> | |||
| | | bioavailability = ~80% (oral)<ref name="vistaril-label" /> | ||
| | | pregnancy = Limited human data; older agent with substantial use experience; some signal for first-trimester exposure but not conclusive.{{citation needed}} | ||
| | | legal = [[USLegal:Prescription only|Rx-only]] in US. Not a controlled substance, which is a meaningful clinical advantage over the benzodiazepine alternatives for short-term anxiety<ref name="vistaril-label" /> | ||
| | | mechanism = <vote slug="hydroxyzine-mech-claim">First-generation H1 histamine receptor antagonist with central nervous system penetration producing sedation. Additional 5-HT2A receptor antagonism, α1-adrenergic antagonism, and anticholinergic effects contribute to the sedative, anxiolytic, and antiemetic activity. Crucially, hydroxyzine has '''no GABA receptor activity''', so it carries no tolerance to anxiolytic effect, no withdrawal syndrome, no dependence liability, and no controlled-substance status, distinguishing it sharply from the benzodiazepine alternatives.</vote> '''QT prolongation''' risk at high doses prompted the FDA's 2015 caution against use in patients with prolonged QT or with concurrent QT-prolonging medicines<ref name="vistaril-label" />. | ||
| | |||
| | |||
| | |||
| | |||
| | |||
| | |||
| | |||
| | |||
| | |||
}} | }} | ||
== References == | |||
<references /> | |||
[[Category:Antihistamines]] | |||
[[Category:Anxiolytics]] | [[Category:Anxiolytics]] | ||
[[Category:Antipruritics]] | |||
[[Category:Sleep aids]] | |||
Latest revision as of 06:32, 23 May 2026
Hydroxyzine (hydrochloride; pamoate salt)
Vistaril (pamoate), Atarax (HCl, discontinued in US as brand)
Experience
No personal reports yet
No clinical reports yet
Log in to add your own experience.
Problems
No problems yet. Be the first to suggest one.
+ Add a problemTitration strategies
No titration strategies yet. Be the first to suggest one.
Effects
No effects listed yet. Be the first to suggest one.
Relevant anecdote
No anecdotes yet. Share a relevant one.
Relevant Literature
No literature entries yet.
Log in to submit relevant literature.
Summary
Common uses
Anxiety symptoms (FDA, short-term)0, Pruritus from allergic conditions (FDA)0, Preoperative sedation (FDA)0, Nausea and vomiting (FDA, IM only)0, Insomnia (off-label)0, Acute alcohol withdrawal adjunct (off-label)0, Pediatric acute agitation (off-label)0
Pharmacy
Starting dose
Anxiety: 25-50 mg PO QID. Pruritus: 25 mg PO TID-QID. Insomnia: 25-50 mg PO at bedtime. Pediatric: 50-100 mg/day divided
Preparations
Tablets 10, 25, 50 mg (HCl); capsules 25, 50, 100 mg (pamoate); oral suspension 25 mg/5 mL; injection 25, 50 mg/mL (IM only, never IV)
US FDA Max
400 mg/day theoretical; in practice rarely exceeds 200 mg/day
Pharmacology
Routes
Oral, intramuscular
Onset
15-30 minutes (oral)
Duration
4-6 hours
Half-life
14-25 hours (longer in elderly and hepatic impairment)[1]
Bioavailability
~80% (oral)[1]
Pregnancy
Limited human data; older agent with substantial use experience; some signal for first-trimester exposure but not conclusive.[citation needed]
Legal status
Purported mechanism
First-generation H1 histamine receptor antagonist with central nervous system penetration producing sedation. Additional 5-HT2A receptor antagonism, α1-adrenergic antagonism, and anticholinergic effects contribute to the sedative, anxiolytic, and antiemetic activity. Crucially, hydroxyzine has no GABA receptor activity, so it carries no tolerance to anxiolytic effect, no withdrawal syndrome, no dependence liability, and no controlled-substance status, distinguishing it sharply from the benzodiazepine alternatives.0 QT prolongation risk at high doses prompted the FDA's 2015 caution against use in patients with prolonged QT or with concurrent QT-prolonging medicines[1].
References
- ↑ 1.0 1.1 1.2 1.3 FDA Prescribing Information, Vistaril (hydroxyzine pamoate), Pfizer, current revision. https://www.accessdata.fda.gov/drugsatfda_docs/label/2009/011459s045lbl.pdf