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    Alprazolam molecular structure

    Alprazolam Stats & Data

    Bars Xans Xanax Tafil Kalma prazolam ksalol niravam
    Chemical Class Benzodiazepine
    Psychoactive Class Depressant
    Half-Life 6–27 hours (average ~12 hours)

    Interaction Warnings

    dissociatives

    This combination can result in an increased risk of vomiting during unconsciousness and death from the resulting suffocation. If this occurs, users should attempt to fall asleep in the recovery position or have a friend move them into it.

    stimulants

    It is dangerous to combine benzodiazepines with stimulants due to the risk of excessive intoxication. Stimulants decrease the sedative effect of benzodiazepines, which is the main factor most people consider when determining their level of intoxication. Once the stimulant wears off, the effects of benzodiazepines will be significantly increased, leading to intensified disinhibition as well as other effects.

    Pharmacology

    DrugBank
    State Solid

    Description

    Alprazolam is a triazolobenzodiazepine indicated for the treatment of anxiety and panic disorders. It is mainly metabolized by CYP3As and so is contraindicated with CYP3A inhibitors like ketoconazole and itraconazole. Benzodiazepine treatment should be stopped gradually by tapering down a patient's dose to avoid withdrawal symptoms. Alprazolam's adverse effects are generally related to the sedation it can cause. Alprazolam has been mixed with alcohol as a drug of abuse to potentiate the sedative effects of the drug which may lead to coma and death. Alprazolam was given FDA approval on October 16, 1981.

    Mechanism of Action

    Neurotransmission relies on excitatory and inhibitory signalling. γ-aminobutyric acid (GABA) type-A receptors (GABAARs) are members of the pentameric ligand-gated ion channel (PLGIC) superfamily located synaptically and perisynaptically to mediate phasic inhibition and extrasynaptically to mediate tonic inhibition. GABAARs comprise a variety of subunits from a homologous family whose members are named based on sequence identity as one of α1-6, β1-3, γ1-3, δ, ε, θ, π, and ρ1-3. Each subunit possesses an extracellular (ECD), transmembrane (TMD), and intracellular (ICD) domain; inter-subunit interfaces are the primary points of neurotransmitter and modulator binding, described by coordination of the principal (+) and complementary (-) sites in each subunit. Binding of GABA to GABAARs induces pore opening, rapid flow of chloride ions, and synaptic hyperpolarization, which in turn manifests as an inhibitory signal. 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. In general, any receptors containing an αxz 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.

    Pharmacodynamics

    Alprazolam is a benzodiazepine that binds γ-aminobutyric acid (GABA) type-A receptors (GABAARs) to enhance their inhibitory effect on neurotransmission, specifically in the brain. Concomitant use with opioids may result in profound sedation, respiratory depression, coma, and death; patients taking benzodiazepines and opioids concurrently may require lower doses of one or both medications, depending on their clinical situation. Patients with pre-existing impaired respiratory function are at increased risk of adverse effects including death during treatment with benzodiazepines. In addition, due to its CNS depressant effects, patients taking alprazolam should avoid operating heavy machinery or driving and should avoid other CNS depressants such as alcohol. As with other benzodiazepines, alprazolam carries a risk of abuse, misuse, and addiction, which is higher in predisposed individuals and may require strict monitoring. Cessation of therapy may result in acute or protracted withdrawal symptoms, which may be life-threatening; the patient dose should be gradually tapered whenever discontinuation or reduced dosage are necessary. Newborns born to mothers using alprazolam later in pregnancy may suffer from sedation and withdrawal symptoms.

    Metabolism

    Alprazolam is metabolized to less effective metabolites by various CYPs including CYP3A4, CYP3A5, CYP3A7, and CYP2C9. The majority of alprazolam metabolism is mediated by hydroxylation via CYP3As. 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.

    Absorption

    Alprazolam administered orally is rapidly absorbed in the gastrointestinal tract, reaching Cmax in about 1.8 (1-2) hours. Absorption is high, resulting in an oral bioavailability of 84-91%. A 1 mg oral dose results in a Cmax of 12-22 μg/L. 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. 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.

    Toxicity

    Alprazolam overdose can present as sleepiness, confusion, poor coordination, slow reflexes, coma, and death. Taking alprazolam with alcohol lowers the threshold for overdose. Patients should have their respiration, pulse, and blood pressure monitored. Patients can be treated by gastric lavage and intravenous fluids.. If hypotension occurs, patients may be treated with vasopressors. In known, or suspected overdoses, patients can be given the benzodiazepine receptor antagonist flumazenil in addition to other methods of management. Oral LD50 in rats is 331-2171mg/kg.

    Indication

    Alprazolam is indicated for the acute treatment of generalized anxiety disorder in adults. Alprazolam is also indicated, either as a standard or extended-release formulation, for the treatment of panic disorder with or without agoraphobia in adults. Alprazolam may also be prescribed off-label for insomnia, premenstrual syndrome, and depression.

    Half-life

    Alprazolam has a mean plasma elimination half-life of 11.2 hours in healthy patients (range 6.3-26.9 hours). 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. The half-life is 25% higher in Asian patients compared to Caucasians. Other studies have shown the half-life to be 9-16h. The extended-release formulation has a half-life of 10.7-15.8 hours in healthy adult patients.

    Protein Binding

    Alprazolam is ~80% protein-bound in serum. The majority of this protein binding is to serum albumin. Alprazolam is also bound to alpha1-acid glycoprotein with low frequency.

    Elimination

    Alprazolam is mainly eliminated in the urine. A large portion of the dose is eliminated as unmetabolized alprazolam. <10% of the dose is eliminated as alpha-hydroxy-alprazolam and 4-hydroxy-alprazolam.

    Volume of Distribution

    Alprazolam has a volume of distribution following oral administration of 0.8-1.3L/kg. Alprazolam crosses the blood-brain barrier.

    Clearance

    A 0.8 mg oral dose of alprazolam had a clearance of 0.90 ± 0.21 mL/min/kg, which increased to 2.13 ± 0.54 mL/min/kg when coadministered with the strong CYP3A4 inducer carbamazepine. Other studies have demonstrated a clearance of 0.70-1.5mL/min/kg.

    Receptor Profile

    Receptor Actions

    Modulators
    GABA-A receptor positive allosteric modulator (benzodiazepine site)

    Receptor Binding

    Translocator protein agonist

    History & Culture

    1971–1981

    Alprazolam was first synthesized in 1971 by J.B. Hester at the Upjohn Company, a pharmaceutical manufacturer that would later become part of Pfizer. The compound was developed as a triazolobenzodiazepine, featuring a triazole ring fused to the core benzodiazepine structure. Following its synthesis, alprazolam was patented in the United States in 1976. The drug received approval from the U.S. Food and Drug Administration on October 16, 1981, for the treatment of panic disorder and generalized anxiety disorder. It was subsequently marketed under the brand name Xanax in the United States, with various other brand names used internationally including Tafil, Kalma, Ksalol, and Niravam.

    Alprazolam has become the most commonly prescribed and misused benzodiazepine in the United States. It has consistently ranked as the most prescribed psychiatric medication in the country, with prescriptions exceeding 40 million annually. This widespread medical use has contributed to its significant presence in both clinical and recreational contexts. The drug's high binding affinity, potency, and rapid onset of effects have contributed to its abuse potential. It has accumulated numerous street names reflecting its cultural prominence, including "Xannies," "Bars," "Z-bars," "Handlebars," and "Footballs," with the latter terms often referencing the shape of different tablet formulations.

    Subjective Effect Notes

    physical: The physical effects of alprazolam can be broken down into several components which progressively intensify proportional to dosage.

    cognitive: The cognitive effects of alprazolam can be broken down into several components which progressively intensify proportional to dosage. The general head space of alprazolam is described by many as one of intense sedation, relaxation, anxiety suppression and decreased inhibition. It contains a large number of typical depressant cognitive effects. Paradoxical reactions to benzodiazepines such as increased seizures (in epileptics), aggression, increased anxiety, violent behavior, loss of impulse control, irritability and suicidal behavior sometimes occur (although they are rare in the general population, with an incidence rate below 1%). These paradoxical effects occur with greater frequency in recreational abusers, individuals with mental disorders, children, and patients on high-dosage regimes.

    Effect Profile

    Curated + 369 Reports
    Benzodiazepine 6.7

    Strong anxiolysis with moderate sedation and cognitive impairment, low euphoria

    Anxiolysis×3
    9 4/20
    Sedation / Relaxation×2
    74.1 7/20
    Motor / Cognitive Impairment×1
    74.7 9/20
    Euphoria / Mood Lift×1
    34.0 13/20
    Catalog Erowid

    User Experiences

    Anxiolysis "but I find valium to be the most recreational or euphoric benzo because of the nice muscle relaxation it provides." Bluelight
    Sedation "I was extremely relaxed but absolutely hated the feeling." Bluelight
    Cognitive Impairment "They also cause amnesia so it's not an unusual situation to wake up bruised and confused, only for your friend to fill you in about how you picked a fight with a bouncer, tried to kiss your best..." Bluelight

    Tolerance & Pharmacokinetics

    drugs.wiki
    Half-Life
    6–27 hours (average ~12 hours)
    Addiction Potential
    High. Alprazolam has a significant risk of dependence and addiction, especially with prolonged or high-dose use. Withdrawal can be severe and potentially dangerous.

    Experience Report Analysis

    Erowid BlueLight
    323 Reports
    1995–2025 Date Range
    124 With Age Data
    30 Effects Detected

    Demographics

    Gender Distribution

    Age Distribution

    Reports Over Time

    Effect Analysis

    Erowid + Bluelight

    Effects aggregated from 369 experience reports (323 Erowid + 46 Bluelight)

    369 Reports
    106 Effects Detected
    36 Positive
    47 Adverse
    23 Neutral

    Effect Sentiment Distribution

    Confidence Distribution

    Positive Effects 36

    Anxiety Suppression 41.5% 88%
    Sedation 29.0% 86%
    Euphoria 27.1% 84%
    Empathy 23.2% 70%
    Stimulation 18.1% 90%
    Contentment 17.4% 82%
    Music Enhancement 12.7% 88%
    Color Enhancement 11.8% 70%
    Sociability Enhancement 10.9% 83%
    Tactile Enhancement 8.7% 80%
    Focus Enhancement 8.7% 80%
    Muscle Relaxation 6.5% 83%
    Body Temperature Change 6.5% 82%
    Motor Enhancement 6.5% 73%
    Body High 5.7% 83%
    Fractal Imagery 4.3% 92%
    Surface Breathing 4.3% 88%
    Joy 4.3% 88%
    Thought Deceleration 4.3% 85%
    Bliss 4.3% 95%

    Adverse Effects 47

    Amnesia 50.0% 91%
    Ataxia 23.9% 84%
    Confusion 23.0% 84%
    Memory Suppression 20.8% 84%
    Thought Disorganization 19.6% 81%
    Disinhibition 19.6% 83%
    Hypersomnia 17.4% 86%
    Motor Impairment 11.4% 85%
    Focus Suppression 10.9% 78%
    Nausea 10.6% 95%
    Body Load 8.7% 79%
    Fear 8.7% 86%
    Vomiting 8.7% 89%
    Emotional Blunting 6.5% 77%
    Depersonalization 6.5% 78%
    Irritability 6.5% 78%
    Seizure 5.3% 70%
    Muscle Tension 5.3% 70%
    Sadness 4.3% 76%
    Dizziness 4.3% 88%

    Dose-Response Correlation

    How effect frequency changes across dose levels

    View data table
    Effect Common (n=60) Strong (n=13) Heavy (n=113)
    Anxiety Suppression 36.7% 53.8% 43.4%
    Sedation 33.3% 38.5% 32.7%
    Euphoria 30.0% 15.4% 31.9%
    Visual Distortions 31.7% 23.1% 11.5%
    Hospital 8.3% 30.8% 17.7%
    Stimulation 30.0% 0% 18.6%
    Confusion 23.3% 23.1% 27.4%
    Memory Suppression 15.0% 23.1% 27.4%
    Empathy 26.7% 23.1% 21.2%
    Music Enhancement 20.0% 23.1% 10.6%
    Dissociation 21.7% 0% 6.2%
    Nausea 18.3% 0% 8.0%
    Auditory Effects 18.3% 15.4% 12.4%
    Tactile Enhancement 15.0% 15.4% 5.3%
    Color Enhancement 13.3% 15.4% 11.5%

    Subjective Effect Ontology

    Experience Reports

    Structured effect tags extracted from 369 Erowid & Bluelight experience reports using a controlled vocabulary of 220+ canonical effects across 15 domains.

    Emotional

    anxiety suppression 153 41.5% euphoria 100 27.1%

    Motor

    sedation 107 29.0%

    3 unique effects extracted · Derived from Erowid & Bluelight reports

    Dose–Effect Mapping

    Experience Reports

    How reported effects shift across dose tiers, based on 323 experience reports.

    Oral dose range: 1.0–3.5 mg (median 2.0 mg)
    Effect Common (n=60) Strong (n=13) Heavy (n=113)
    anxiety suppression
    37%
    54%
    43%
    sedation
    33%
    38%
    33%
    euphoria
    30%
    15%
    32%
    visual distortions
    32%
    23%
    12%
    hospital
    8%
    31%
    18%
    stimulation
    30%
    19%
    confusion
    23%
    23%
    27%
    memory suppression
    15%
    23%
    27%
    empathy
    27%
    23%
    21%
    music enhancement
    20%
    23%
    11%
    dissociation
    22%
    6%
    nausea
    18%
    8%
    auditory effects
    18%
    15%
    12%
    tactile enhancement
    15%
    15%
    5%
    color enhancement
    13%
    15%
    12%
    seizure
    3%
    15%
    4%
    motor impairment
    15%
    13%
    muscle tension
    13%
    3%
    closed-eye visuals
    13%
    7%
    focus enhancement
    13%
    9%

    Showing top 20 of 32 effects

    Risk Escalation

    Sentiment Analysis

    Average frequency of positive vs adverse effects across dose tiers

    Common n=60
    10 positive 16.8% 12 adverse 13.2%
    Strong n=13
    5 positive 18.5% 4 adverse 28.9%
    Heavy n=113
    10 positive 11.5% 14 adverse 10.4%
    View effect breakdown

    Adverse Effects

    Effect Common (n=60) Strong (n=13) Heavy (n=113) Change
    Anxiety Suppression
    37%
    54%
    43%
    +18%
    Confusion
    23%
    23%
    27%
    +17%
    Memory Suppression
    15%
    23%
    27%
    +82%
    Nausea
    18%
    8%
    -56%
    Seizure
    3%
    15%
    4%
    6%
    Motor Impairment
    15%
    13%
    -11%
    Muscle Tension
    13%
    3%
    -79%
    Jaw Clenching
    8%
    2%
    -78%
    Pupil Dilation
    8%
    4%
    -57%
    Sweating
    7%
    4%
    -47%
    Increased Heart Rate
    7%
    5%
    -20%
    Headache
    3%
    2%
    -45%
    Psychosis
    3%
    0%
    Appetite Suppression
    2%
    0%

    Positive Effects

    Effect Common (n=60) Strong (n=13) Heavy (n=113) Change
    Euphoria
    30%
    15%
    32%
    6%
    Stimulation
    30%
    19%
    -37%
    Empathy
    27%
    23%
    21%
    -20%
    Music Enhancement
    20%
    23%
    11%
    -47%
    Tactile Enhancement
    15%
    15%
    5%
    -64%
    Color Enhancement
    13%
    15%
    12%
    -13%
    Focus Enhancement
    13%
    9%
    -33%
    Introspection
    12%
    2%
    -84%
    Body High
    5%
    4%
    -30%
    Pain Relief
    3%
    2%
    -45%

    Dosage Distribution

    Dose distribution from experience reports

    Oral

    Median: 2.0 mg IQR: 1.0–3.5 mg n=191

    Insufflated

    Median: 2.0 mg IQR: 1.0–3.0 mg n=16

    Real-World Dose Distribution

    62K Doses

    From 670 individual dose entries

    Oral (n=517)

    Median: 1.5mg 25th: 1.0mg 75th: 2.0mg 90th: 4.0mg
    mg/kg median: 0.02 mg/kg 75th: 0.038

    Sublingual (n=7)

    Median: 0.5mg 25th: 0.25mg 75th: 0.5mg 90th: 0.7mg
    mg/kg median: 0.006 mg/kg 75th: 0.008

    Insufflated (n=41)

    Median: 1.5mg 25th: 1.0mg 75th: 2.0mg 90th: 3.0mg
    mg/kg median: 0.022 mg/kg 75th: 0.033

    Common Combinations

    Most co-occurring substances in experience reports

    Form / Preparation

    Most common forms and preparations reported

    Body-Weight Dosing

    Dose relative to body weight from reports with weight data

    Oral

    Median: 0.026 mg/kg IQR: 0.014–0.049 mg/kg n=190

    Insufflated

    Median: 0.028 mg/kg IQR: 0.015–0.036 mg/kg n=16

    Redose Patterns

    Redosing behavior across 285 reports

    24.6% Redosed
    1.4 Avg Doses
    75m Median Interval

    Benzodiazepine Equivalence

    0.5 mg Alprazolam = 10.0 mg Diazepam
    Potency ratio 20.0
    Bioavailability Oral 80-90%

    Alprazolam - 0.5mg ~=10mg Diazepam.

    When taken for a long period of time, abrupt discontinuation is highly unadvised. Avoid combining other depressants such as Alcohol.

    Legal Status

    United Nations Convention on Psychotropic Substances (Schedule IV)
    Country Status Notes
    Australia Schedule 8 Originally classified as Schedule 4 (prescription only), alprazolam was rescheduled to Schedule 8 in January 2014, subjecting it to more rigorous prescribing requirements. Maximum in-house consumption is limited to 5 mg per day.
    Austria Prescription Only Legal for medical use under the Arzneimittelgesetz (AMG). Possession or sale without a valid prescription is prohibited under the Suchtmittelgesetz (SMG).
    Belgium Prescription Only Benzodiazepines including alprazolam are regulated as prescription medications under Belgian pharmaceutical law.
    Canada Schedule IV (CDSA) Controlled under Schedule IV of the Controlled Drugs and Substances Act. Requires a valid prescription for lawful possession.
    Czech Republic Schedule IV (List 7) Controlled substance under Nařízení vlády č. 463/2013 Sb. Available exclusively with a standard prescription (without blue stripe designation).
    France List I Classified as a List I substance under French pharmaceutical law. Available only by prescription and illegal to purchase without one.
    Germany Anlage III BtMG Controlled under Anlage III of the Betäubungsmittelgesetz (Narcotics Act) since August 1, 1986. Requires a narcotic prescription form, except for preparations containing up to 1 mg per dosage unit. Maximum of 50 dosage units may be dispensed together.
    Ireland Schedule 4 Classified as a Schedule 4 controlled medicine. Requires a valid prescription for legal possession.
    Italy Schedule IV (Tabella 4) Listed in Tabella 4 under the Testo unico sulla droga (D.P.R. 309/90). For medical prescriptions, falls under Pharmaceuticals section B and E.
    Mexico Schedule II Classified as a Schedule II controlled substance requiring a prescription for legal acquisition.
    Netherlands List 2 (Opiumwet) Controlled under List 2 of the Opium Law. Available for legitimate medical use with a valid prescription.
    Russia Schedule III Classified as a Schedule III controlled substance since 2013. Requires prescription for legal possession.
    South Africa Schedule 5 Listed as a Schedule 5 substance, making it available by prescription only. Marketed under the brand name Zopax.
    Sweden List IV (Schedule 4) Regulated as a prescription medication under List IV of the Narcotics Drugs Act (Narkotikastrafflagen) of 1968.
    Switzerland Verzeichnis B Specifically named as a controlled substance under Verzeichnis B of Swiss narcotics legislation. Available by prescription in 0.25, 0.5, 1, and 2 mg dose units.
    Turkey Green Prescription Designated as a 'green prescription' medication, indicating stricter prescribing controls. Possession or sale without prescription is illegal.
    United Kingdom Class C (Schedule 4, Part I) Classified as a Class C drug under the Misuse of Drugs Act 1971 and listed under Schedule 4, Part I (CD Benz POM) of the Misuse of Drugs Regulations 2001. Requires a valid prescription for lawful possession. Not available through the National Health Service.
    United States Schedule IV Assigned to Schedule IV of the Controlled Substances Act by the Drug Enforcement Administration. Received FDA approval on October 16, 1981. Illegal to sell without a license and illegal to possess without a valid prescription.

    Harm Reduction

    drugs.wiki

    Do not combine alprazolam with opioids, alcohol, or other sedatives; this combination greatly increases the risk of respiratory depression, coma, and death. A boxed warning applies to the class for opioid co‑use. Alprazolam is primarily metabolized by CYP3A; strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, clarithromycin, nefazodone, fluvoxamine) and grapefruit can raise levels markedly; strong inducers (e.g., carbamazepine, phenytoin, rifampin, St. John’s wort) can lower levels and precipitate withdrawal or loss of effect. Street “Xanax” bars are frequently misrepresented; drug‑checking services have repeatedly found potent designer benzodiazepines (e.g., flualprazolam, norflurazepam) or other unexpected actives in tablets sold as alprazolam. Use professional drug checking where available and avoid assuming imprint/appearance equals identity. Do not stop suddenly after repeated dosing; benzodiazepine withdrawal can include seizures and delirium. Tapering should be gradual and medically supervised; flumazenil can precipitate acute withdrawal and seizures in dependent users and is generally avoided outside specific monitored indications. Alprazolam impairs attention, memory, and coordination; avoid driving or hazardous tasks while affected and after high or interacting doses. Avoid non‑oral routes: crushing tablets for injection/insufflation introduces fillers that can damage tissue and vasculature, and increases risk without added safety. Rapid onset and short/moderate duration encourage redosing and can accelerate tolerance; spacing use and conservative dosing reduce risk.

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