Alprazolam 500microgram tablets
Requires a prescription from a doctor or prescriber
Minimal controls; includes benzodiazepines and anabolic steroids
Legal requirements and restrictions
Benzodiazepines and similar medicines. Subject to minimal controlled drug requirements.
Legal requirements
- Prescriptions valid for 28 days
- No controlled drugs register required
- No safe custody requirements
- Record keeping requirements for imports/exports
Other medicines in this category
Official documents, adverse reaction reporting, and safety monitoring
Report a side effect
Submit a Yellow Card report to the MHRA
Safety monitoring data
Yellow Card reports
The MHRA Yellow Card scheme collects reports of suspected side effects from healthcare professionals and patients. View the Drug Analysis Profile (iDAP) for real-world adverse reaction data.
View Drug Analysis Profile
Suspected adverse reactions reported for Alprazolam
Browse all iDAP reports
Interactive Drug Analysis Profiles for all medicines
Report a side effect
Submit a Yellow Card report to the MHRA
Data from the MHRA Yellow Card scheme. A reported reaction does not necessarily mean the medicine caused it. Contains public sector information licensed under the Open Government Licence v3.0.
EudraVigilance
The European Medicines Agency (EMA) collects suspected adverse reaction reports from across the EU/EEA through the EudraVigilance system. Search for safety data on this medicine.
View EudraVigilance report
Suspected adverse reactions reported for Alprazolam
About EudraVigilance
Learn about EU pharmacovigilance and safety monitoring
EudraVigilance data is published by the European Medicines Agency (EMA). A suspected adverse reaction is not necessarily caused by the medicine.
1 branded products available
MHRA licensed products
View all licensed products for Alprazolam on the MHRA register
Xanax 500microgram tablets
WHO defined daily dose (DDD)
1 mg
Not a recommended dose. The DDD is the assumed average maintenance dose per day for a drug used for its main indication in adults. It is a statistical measure used for research and comparison purposes only.
Source: WHO Collaborating Centre for Drug Statistics Methodology, distributed via the NHS dm+d supplementary mapping files (NHSBSA). Contains public sector information licensed under the Open Government Licence v3.0.
Therapeutically similar medicines
Similarity is based on WHO Anatomical Therapeutic Chemical (ATC) classification and on a factual NHS dm+d therapeutic-grouping code prefix. Source data: NHS dm+d via TRUD (OGL v3.0), WHO ATC/DDD Index.
NHS prescribing volume and spending trends
Guidelines from the National Institute for Health and Care Excellence
NICE clinical guidance(1)
Source: National Institute for Health and Care Excellence (NICE). Contains public sector information licensed under the Open Government Licence v3.0.
Check stock at pharmacies and supply information
Pharmacy stock checkers
Search for this medicine at major UK pharmacy chains. These links open the retailer's own website — results depend on their current online catalogue.
Supply & safety information
Official UK regulator monitoring and safety alerts
Pharmacy links redirect to the retailer's own search and do not represent real-time stock levels. Shortage and safety information sourced from MHRA drug safety updates (gov.uk, Crown Copyright under OGL v3.0).
Codes for healthcare professionals and prescribing systems
These codes are used by healthcare IT systems and prescribers to identify this medicine.
NHS UK identifiers
Browse tools
SNOMED CT and dm+d codes from NHS TRUD (Technology Reference data Update Distribution), licensed under the Open Government Licence v3.0. ATC codes from the WHO Collaborating Centre for Drug Statistics Methodology (whocc.no).
Active and completed clinical studies from ClinicalTrials.gov
Source: ClinicalTrials.gov, a database of the U.S. National Library of Medicine (NLM), National Institutes of Health (NIH). Data accessed via ClinicalTrials.gov API v2. Trial information is provided for research purposes and does not constitute medical advice.
Academic studies and reviews for this medicine's active substance
Showing the 50 most relevant studies.
Reviews & meta-analyses: 10 · Randomised trials: 9 · 1982–2026
Showing the 50 most relevant studies, sorted by most relevant.
J. Almeida, E. W. Grimsley
Annals of Internal Medicine, 1996
- Nonprescription Drugs
- Alprazolam
- Coma
William F. Boyer
International Clinical Psychopharmacology, 1995
- Alprazolam
- Imipramine
- Psychiatric Status Rating Scales
Barbara O. Rothbaum, Matthew Price, Tanja Jovanović, et al.
American Journal of Psychiatry, 2014
- Alprazolam
- Combined Modality Therapy
- Cycloserine
Nassima Ait‐Daoud, Allan Scott Hamby, Sana Sharma, et al.
Journal of Addiction Medicine, 2017
- Prescription Drug Misuse
- Alprazolam
- Anxiety Disorders
Jimmie C. Holland, Gary R. Morrow, Arthur H. Schmale, et al.
Journal of Clinical Oncology, 1991
- Behavior Therapy
- Alprazolam
- Anxiety Disorders
Rae Yuan, David A. Flockhart, John Dikran Balian
The Journal of Clinical Pharmacology, 1999
- Alprazolam
- Data Collection
- Drug Interactions
Jeffrey M. Jonas, M S Cohon
PubMed, 1993
- Alprazolam
- Antidepressive Agents
- Anxiety Disorders
Harm van Marwijk, Gideon Allick, Froukje Wegman, et al.
Cochrane Database of Systematic Reviews, 2012
- Alprazolam
- Antidepressive Agents
- Depression
Samuel Smith, John S. Rinehart, Vilma E. Ruddock, et al.
PubMed, 1987
- Alprazolam
- Clinical Trials as Topic
- Premenstrual Syndrome
Jeffrey M. Jonas, Arthur E. Jr Hearron
Journal of Clinical Psychopharmacology, 1996
- Suicide Prevention
- Alprazolam
- Clinical Trials as Topic
Sources: aggregated from Europe PMC (EMBL-EBI), OpenAlex, Crossref, PubMed and other open scholarly databases. Retracted articles are excluded. Study information is provided for research purposes and does not constitute medical advice.
Pharmacology and chemical data from DrugBank
Key facts
Drug status
Approved
Major interactions
1 found
Half-life
11.2 hours
Mechanism
Neurotransmission relies on excitatory and inhibitory signalling.
Food interactions
4 warnings
Human targets
3 targets
Data: DrugBank · CC BY-NC 4.0
Pharmacokinetics at a glance
Absorption
84-91%
Half-life
11.2 hours
Protein binding
80%
[L34783][L34788]
The majority of this protein binding is to serum albumin.…
Volume of distribution
0.8-1.3L/kg
[A177925]
Alprazolam crosses the blood-brain barrier.
[A18125]
Metabolism
20%
Elimination
10%
[L34783][L34788]
A large portion of the dose is eliminated as unmetabolized alprazolam.
[A177925]
…
Clearance
0.8 mg
Pharmacokinetic data: DrugBank · CC BY-NC 4.0
[L34783]
Alprazolam is also indicated, either as a standard or extended-release formulation, for the treatment of panic disorder with or without agoraphobia in adults.
[L34783][L34788]
Alprazolam may also be prescribed off-label for insomnia, premenstrual syndrome, and depression.
[A177973]
Known interactions with other medicines. Always consult a healthcare professional.
Showing 50 of 1666 interactions
[L34783][L34788]
Taking alprazolam with alcohol lowers the threshold for overdose.
[L34783][L34788]
Patients should have their respiration, pulse, and blood pressure monitored.
[L34783][L34788]
Patients can be treated by gastric lavage and intravenous fluids..
[L34783][L34788]
If hypotension occurs, patients may be treated with vasopressors.
[L34783][L34788]
In known, or suspected overdoses, patients can be given the benzodiazepine receptor antagonist [flumazenil] in addition to other methods of management.
[L34783][L34788]
Oral LD50 in rats is 331-2171mg/kg.[Label]
The most prevalent GABAARs in vivo are the α1β2γ2 receptors, which contain both GABA (β+/α-) and benzodiazepine (BZD, α+/γ-) binding sites in the intersubunit interfaces of the relevant subunits.[A236793][A236798][A236828] In general, any receptors containing an αx/γz interface, where x = 1-3,5 and z = 1-3, have potential high-affinity BZD binding sites, although small sequence differences between subunits may alter binding affinity to individual molecules. The α4 and α6 subunits, in which an otherwise conserved histidine is replaced by arginine, do not bind traditional BZD ligands such as diazepam and hence are considered "diazepam-insensitive".[A236793][A236798][A236828] GABA binding results in a series of conformational changes in the ECDs of GABAAR β subunits, "locking" each to its neighbouring α- interface. The binding of alprazolam in the high-affinity BZD site stabilizes the α+/γ- interface and facilitates the conformational changes that lead to pore opening, hence functioning as a positive allosteric modulator.[A236833]
The exact manner in which GABAAR allosteric modulation mediates the therapeutic and unwanted effects of benzodiazepines remains unclear.[A177973][A18125] Earlier studies suggested that the primary factor was the α subunit composition, with α1-containing receptors mediating the sedative effects, α2/3-containing receptors the anxiolytic effects, and α5-containing receptors the memory effects of benzodiazepines.[A236838] More recent studies suggest a more complex set of factors including subunit composition, physiological location, neuronal circuit, and nerve cell type.[A236843] To further complicate matters, there may be up to five distinct BZD binding sites on GABAARs, with site 1 corresponding to the classical high-affinity α+/γ- interface. The effects of binding at sites 2-4 are not fully understood and likely impart greater complexity to benzodiazepine pharmacological action.[A236798][A236828]
How the body processes this drug — absorption, distribution, metabolism, and elimination
[A177925][L34783]
The extended-release formulation of alprazolam (XANAX XR) has similar absorption, bioavailability, and pharmacokinetics as the standard release, with the exception that the Tmax is ~10 hours compared to 1-2 hours.
Temporal dosing alters these parameters, with Cmax increasing by 30% and Tmax decreasing by one hour when dosed at night as opposed to in the morning.
[L34788]
Food has an effect on alprazolam absorption; a high-fat meal up to two hours before dosing increases the Cmax by ~25% and either a reduction (food consumed immediately prior to dosing) or increase (food consumed after dosing) of ~1/3 in Tmax. Neither the AUC nor half-life are appreciably affected by eating.
[L34788]
[L34783]
The mean half-life is 16.3 hours (range 9.0-26.9 hours) in the elderly, 21.8 hours (range 9.9-40.4 hours) in obese patients, and 19.7 hours (range 5.8-65.3 hours) in patients with alcoholic liver disease.
[L34783]
The half-life is 25% higher in Asian patients compared to Caucasians.
[L34783]
Other studies have shown the half-life to be 9-16h.
[A177925]
The extended-release formulation has a half-life of 10.7-15.8 hours in healthy adult patients.
[L34788]
[L34783][L34788]
The majority of this protein binding is to serum albumin.
[A177922][L34783][L34788]
Alprazolam is also bound to alpha1-acid glycoprotein with low frequency.
[A177925]
[A177925]
Alprazolam crosses the blood-brain barrier.
[A18125]
[A415][A14775][L162][L34783][L34788]
The majority of alprazolam metabolism is mediated by hydroxylation via CYP3As.
[A415][A14775][A177925][L162][L34783][L34788]
4-hydroxyalprazolam has 20% the binding affinity of the parent drug, alpha-hydroxyalprazolam has 66% the affinity, and the benzophenone metabolite has <1% the affinity.
[A177925][L34783][L34788]
[L34783][L34788]
A large portion of the dose is eliminated as unmetabolized alprazolam.
[A177925]
<10% of the dose is eliminated as alpha-hydroxy-alprazolam and 4-hydroxy-alprazolam.
[A177925]
[L34783][L34788]
Other studies have demonstrated a clearance of 0.70-1.5mL/min/kg.
[A177925]
Proteins and enzymes this drug interacts with in the body
PMID:10449790 PMID:16412217
GABA-gated chloride channels, also named GABA(A) receptors (GABAAR), consist of five subunits arranged around a central pore and contain GABA active binding site(s) located at the alpha and beta subunit interfaces (By similarity). When activated by GABA, GABAARs selectively allow the flow of chloride anions across the cell membrane down their electrochemical gradient PMID:10449790 PMID:16412217
Was initially identified as peripheral-type benzodiazepine receptor; can also bind isoquinoline carboxamides PMID:1847678
Enzymes involved in drug metabolism — important for understanding drug interactions
Proteins that carry this drug through the body
PMID:19021548
Major calcium and magnesium transporter in plasma, binds approximately 45% of circulating calcium and magnesium in plasma (By similarity).
Potentially has more than two calcium-binding sites and might additionally bind calcium in a non-specific manner (By similarity). The shared binding site between zinc and calcium at residue Asp-273 suggests a crosstalk between zinc and calcium transport in the blood (By similarity). The rank order of affinity is zinc > calcium > magnesium (By similarity).
Binds to the bacterial siderophore enterobactin and inhibits enterobactin-mediated iron uptake of E.coli from ferric transferrin, and may thereby limit the utilization of iron and growth of enteric bacteria such as E.coli .
PMID:6234017
Does not prevent iron uptake by the bacterial siderophore aerobactin PMID:6234017
Appears to function in modulating the activity of the immune system during the acute-phase reaction
ATC N05BA12
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Show
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Linked compound data from DrugBank Open Data (CC BY-NC 4.0)
Alprazolam
Additional database identifiers
Drugs Product Database (DPD)
2072
ChemSpider
2034
BindingDB
50001728
PDB
08H
ZINC
ZINC000000000903
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4075
GenAtlas
GABRA1
GeneCards
GABRA1
GenBank Gene Database
X13584
GenBank Protein Database
31631
Guide to Pharmacology
404
UniProt Accession
GBRA1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4076
GenAtlas
GABRA2
GeneCards
GABRA2
GenBank Gene Database
S62907
GenBank Protein Database
386422
Guide to Pharmacology
405
UniProt Accession
GBRA2_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4077
GenAtlas
GABRA3
GeneCards
GABRA3
GenBank Gene Database
S62908
GenBank Protein Database
386424
Guide to Pharmacology
406
UniProt Accession
GBRA3_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4078
GenAtlas
GABRA4
GeneCards
GABRA4
GenBank Gene Database
U30461
GenBank Protein Database
905393
Guide to Pharmacology
407
UniProt Accession
GBRA4_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4079
GenAtlas
GABRA5
GeneCards
GABRA5
GenBank Gene Database
L08485
GenBank Protein Database
182916
Guide to Pharmacology
408
UniProt Accession
GBRA5_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4080
GenAtlas
GABRA6
GeneCards
GABRA6
GenBank Gene Database
S81944
GenBank Protein Database
1470364
Guide to Pharmacology
409
UniProt Accession
GBRA6_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4081
GenAtlas
GABRB1
GeneCards
GABRB1
GenBank Gene Database
X14767
GenBank Protein Database
31635
UniProt Accession
GBRB1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4082
GenAtlas
GABRB2
GeneCards
GABRB2
GenBank Gene Database
S67368
GenBank Protein Database
455946
UniProt Accession
GBRB2_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4083
GenAtlas
GABRB3
GeneCards
GABRB3
GenBank Gene Database
M82919
GenBank Protein Database
182925
Guide to Pharmacology
412
UniProt Accession
GBRB3_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4084
GeneCards
GABRD
GenBank Gene Database
AF016917
GenBank Protein Database
2388693
UniProt Accession
GBRD_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4085
GeneCards
GABRE
GenBank Gene Database
U66661
GenBank Protein Database
1857126
UniProt Accession
GBRE_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4086
GeneCards
GABRG1
GenBank Gene Database
AK122845
GenBank Protein Database
193783776
UniProt Accession
GBRG1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4087
GeneCards
GABRG2
GenBank Gene Database
X15376
GenBank Protein Database
31637
UniProt Accession
GBRG2_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4088
GeneCards
GABRG3
GenBank Gene Database
S82769
GenBank Protein Database
1754749
UniProt Accession
GBRG3_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4089
GeneCards
GABRP
GenBank Gene Database
U95367
GenBank Protein Database
2197001
UniProt Accession
GBRP_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:14454
GeneCards
GABRQ
GenBank Gene Database
AF189259
GenBank Protein Database
7861736
UniProt Accession
GBRT_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4075
GenAtlas
GABRA1
GeneCards
GABRA1
GenBank Gene Database
X13584
GenBank Protein Database
31631
Guide to Pharmacology
404
UniProt Accession
GBRA1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4076
GenAtlas
GABRA2
GeneCards
GABRA2
GenBank Gene Database
S62907
GenBank Protein Database
386422
Guide to Pharmacology
405
UniProt Accession
GBRA2_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4077
GenAtlas
GABRA3
GeneCards
GABRA3
GenBank Gene Database
S62908
GenBank Protein Database
386424
Guide to Pharmacology
406
UniProt Accession
GBRA3_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4079
GenAtlas
GABRA5
GeneCards
GABRA5
GenBank Gene Database
L08485
GenBank Protein Database
182916
Guide to Pharmacology
408
UniProt Accession
GBRA5_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4086
GeneCards
GABRG1
GenBank Gene Database
AK122845
GenBank Protein Database
193783776
UniProt Accession
GBRG1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4087
GeneCards
GABRG2
GenBank Gene Database
X15376
GenBank Protein Database
31637
UniProt Accession
GBRG2_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:4088
GeneCards
GABRG3
GenBank Gene Database
S82769
GenBank Protein Database
1754749
UniProt Accession
GBRG3_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:1158
GenAtlas
TSPO
GeneCards
TSPO
GenBank Gene Database
M36035
GenBank Protein Database
306883
Guide to Pharmacology
2879
UniProt Accession
TSPO_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2640
GeneCards
CYP3A7
GenBank Gene Database
D00408
GenBank Protein Database
220149
UniProt Accession
CP3A7_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2637
GenAtlas
CYP3A4
GeneCards
CYP3A4
GenBank Gene Database
M18907
Guide to Pharmacology
1337
UniProt Accession
CP3A4_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2623
GenAtlas
CYP2C9
GeneCards
CYP2C9
GenBank Gene Database
AY341248
Guide to Pharmacology
1326
UniProt Accession
CP2C9_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2638
GenAtlas
CYP3A5
GeneCards
CYP3A5
GenBank Gene Database
J04813
GenBank Protein Database
181346
Guide to Pharmacology
1338
UniProt Accession
CP3A5_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:399
GenAtlas
ALB
GeneCards
ALB
GenBank Gene Database
V00494
GenBank Protein Database
28590
UniProt Accession
ALBU_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:8498
GenAtlas
ORM1
GeneCards
ORM1
GenBank Gene Database
X02544
GenBank Protein Database
757907
UniProt Accession
A1AG1_HUMAN
HUGO Gene Nomenclature Committee (HGNC)
HGNC:8499
GeneCards
ORM2
GenBank Gene Database
BC015964
GenBank Protein Database
16359000
UniProt Accession
A1AG2_HUMAN
DrugBank citations
If you use DrugBank data in your research, please cite:
- DrugBank 6.02024Recommended citationKnox C., Wilson M., Klinger C.M., et alDrugBank 6.0: the DrugBank Knowledgebase for 2024Nucleic Acids Res. 2024 Jan 552(D1):D1265-D1275
- DrugBank 5.02018Wishart D.S., Feunang Y.D., Guo A.C., et alDrugBank 5.0: a major update to the DrugBank database for 2018Nucleic Acids Res. 2017 Nov 846(D1):D1074-D1082
- DrugBank 4.02014Law V., Knox C., Djoumbou Y., et alDrugBank 4.0: shedding new light on drug metabolismNucleic Acids Res. 2014 Jan 142(1):D1091-7
- DrugBank 3.02011Knox C., Law V., Jewison T., et alDrugBank 3.0: a comprehensive resource for 'omics' research on drugsNucleic Acids Res. 2011 Jan39(Database issue):D1035-41
- DrugBank 2.02008Wishart D.S., Knox C., Guo A.C., et alDrugBank: a knowledgebase for drugs, drug actions and drug targets.Nucleic Acids Research2008 Jan36(Database issue):D901-6
- DrugBank 1.02006Wishart D.S., Knox C., Guo A.C., et alDrugBank: a comprehensive resource for in silico drug discovery and exploration.Nucleic Acids Research2006 Jan 134(Database issue):D668-72