Not yet reviewed — this article is pending editorial review by Lyrea.

Clonazolam

Psychoactive Class

Depressant Sedative Anxiolytic GABAergic Muscle Relaxant

Chemical Class

Clonazolam is a highly potent depressant of the triazolobenzodiazepine class, structurally related to both clonazepam and alprazolam. First synthesized in 1971, it was never marketed pharmaceutically and has been available as a research chemical since the mid-2000s. It is considered to pose higher risks than many other designer benzodiazepines due to its exceptional potency, with strong sedation and amnesia reported at very low doses. Blackouts and dependence are frequently reported concerns.

Dosage & Duration

Dosage

Threshold~50 µg

Light50-200 µg

Moderate200-400 µg

Strong400-500 µg

Heavy500+ µg

Extremely potent; doses as small as 0.5 mg can produce strong sedation and amnesia, and doses above 0.5 mg can cause benzodiazepine overdose in some individuals. Onset may be delayed, with some users feeling little or nothing until 1-2 hours after administration; redosing is inadvisable at any point. Vendors often sell 500 µg products despite this exceeding a common dose.

Duration

Onset10-30 minutes

After Effects1-12 hours

Total6-10 hours

Subjective Effects

Effects vary widely by individual, dose, and context.

Physical

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

Respiratory depression Dizziness Muscle relaxation Motor control loss

Cognitive

The cognitive effects of clonazolam can be broken down into several components which progressively intensify proportional to dosage. The general head space of clonazolam is described by many as one of intense sedation 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.

Amnesia Anxiety suppression Thought deceleration Disinhibition Information processing suppression Euphoria Compulsive redosing

Forked from Subjective Effect Documentation

by Josie KinsSeptember 2015.

Reagent Testing

Expected colorimetric results for common reagent tests. Colors show reaction change over 1–2 minutes.

Zimm(ZI)

Marquis(MQ)

No reaction

Mecke(ME)

No reaction

Mandelin(MD)

No reaction

PROtestkit.eu

Pharmacology

Pharmacodynamics

Clonazolam acts as a positive allosteric modulator of GABA-A receptors at the benzodiazepine binding site, enhancing the activity of the inhibitory neurotransmitter GABA. It is notably potent, proving the most active compound in a series of triazolobenzodiazepines and sometimes effective at doses below 10 μg/kg in mice. The anticonvulsant properties of benzodiazepines may also involve binding to voltage-dependent sodium channels.

Pharmacokinetics

Clonazolam undergoes extensive metabolism in humans. The primary metabolic routes include reduction of the nitro group to form 7-aminoclonazolam (the most abundant urinary metabolite), which is subsequently acetylated to 7-acetaminoclonazolam. Monohydroxylation also occurs, most likely at the α- and 4-positions, yielding hydroxyclonazolam. These metabolites are further conjugated with glucuronic acid.

Interactions

Interactions not written up yet

An unlisted combination is an unknown one, not a safe one. Check a dedicated combination chart before mixing.

Check

TripSit

Tolerance

Full Tolerance

Tolerance to sedative-hypnotic effects can emerge quickly, often after only several days of uninterrupted use. Higher doses accelerate tolerance development, and tolerance may build at different rates for different effects--mood elevation tends to decline faster than sedation.

Cross Tolerance

Benzodiazepines

Baseline Reset

Following cessation, tolerance generally returns to baseline within 7-14 days. However, this timeframe may be significantly longer in cases of prolonged or intensive use, with the duration proportional to the intensity and length of prior consumption.

Harm Potential

Addiction & Dependence

Psychological

Extremely High

Clonazolam is considered extremely psychologically addictive with high abuse potential. Compulsive redosing is commonly reported, and the substance is noted for producing euphoria more frequently than many other benzodiazepines, which may increase its reinforcing properties. Rebound anxiety following use can facilitate cycles of dependence.

Physical

Extremely High

Physical dependence can develop within days of regular use, and in some cases even after a single large dose. Withdrawal is potentially life-threatening and may include anxiety, insomnia, cognitive impairment, elevated blood pressure, increased heart rate, tremor, restlessness, and in severe cases psychosis and seizures. Abrupt discontinuation is strongly discouraged; gradual tapering under medical supervision is recommended.

Psychosis Risk

Psychosis is rare during intoxication but may occur during severe benzodiazepine withdrawal. Paradoxical reactions including aggression, violent behavior, and increased anxiety occur with an incidence below 1% in the general population but are more frequent in recreational abusers, individuals with mental disorders, and those on high-dose regimens.

Seizure Risk

Clonazolam possesses anticonvulsant properties during active use. However, abrupt discontinuation after regular use poses a significant seizure risk that can be life-threatening. Gradual tapering is essential for anyone who has developed physical dependence.

History & Culture

Clonazolam was first synthesized in 1971 by The Upjohn Company, the pharmaceutical corporation that would later bring alprazolam (Xanax) to market. In the original research, the compound was described as the most active substance in the series of triazolobenzodiazepines tested. Despite this notable…

Legality

International

Clonazolam is internationally placed in Schedule IV of the Convention on Psychotropic Substances of 1971. This international result does not itself establish each domestic implementation result above.

By Country

United StatesIllegalSchedule I

Schedules of Controlled Substances: Placement of Clonazolam, Diclazepam, Etizolam, Flualprazolam, and Flubromazolam in Schedule I of the Controlled Substances Act, 91 FR 9985 (Mar. 2, 2026), document 2026-04112⁴¹⁴²

DEA's final rule, effective April 1, 2026, permanently placed clonazolam in Schedule I. It supersedes the prior temporary Schedule I placement and extension through July 26, 2026.

By state

IowaIllegalSchedule I clonazolam

KansasIllegalSchedule I ACSCN 2786

MarylandIllegalSchedule I incorporation

MinnesotaIllegalSchedule I depressant

NebraskaIllegalSchedule I depressant

NevadaIllegalSchedule I

New MexicoIllegalSchedule I depressant (benzodiazepine)

North CarolinaIllegalSchedule I systemic depressant

North DakotaIllegalSchedule I depressant

OregonIllegalState controlled substance listing

AustriaRestrictedPsychotropic substance

Psychotropenverordnung (PV), Anlage 1, Z 2; §§ 1–2²³

The current consolidated PV expressly names Clonazolam in Anlage 1 Z 2. The PV defines annexed substances as psychotropic substances and subjects their manufacture, processing, conversion, acquisition and possession to ministerial authorization, subject to specified exceptions.

CanadaRestrictedSchedule IV benzodiazepine

Controlled Drugs and Substances Act, Schedule IV, item 18⁷

Clonazolam is not expressly named in the current Schedule IV. On the supplied identity as a triazolobenzodiazepine, it falls within Schedule IV item 18's express benzodiazepine-and-derivatives class rule. CDSA ss. 5–7 prohibit Schedule-IV trafficking, import/export, and production except as authorized; simple possession is not prohibited by s. 4(1), which applies only to Schedules I–III.

DenmarkIllegalEuphoric substance — list E

Bekendtgørelse om euforiserende stoffer, BEK nr 405 af 26/03/2026, Bilag 1, liste E, nr. 18; §§ 3 and 6¹⁰¹¹

The current official order expressly lists exact clonazolam on list E. List E substances may only be used for medical and scientific purposes; receipt and possession are allowed only for the specified lawful recipients/cases in § 6.

IrelandIllegalControlled drug

Misuse of Drugs Act 1977 (Controlled Drugs) (Declaration) Order 2022, S.I. No. 176/2022¹⁶

The official Order expressly identifies Clonazolam by its full chemical name and declares every substance in its Schedule a controlled drug for purposes of the Misuse of Drugs Act 1977. The Schedule also covers stereoisomers, esters/ethers, salts, and preparations containing scheduled substances.

JapanIllegalPsychotropic (向精神薬)

Narcotics and Psychotropics Control Act; Cabinet Order Designating Narcotics, Narcotic Raw-Material Plants, Psychotropics and Narcotic/Psychotropic Raw Materials (Cabinet Order No. 238 of 1990), Article 4(38)¹⁹²⁰

Clonazolam is expressly listed as a psychotropic, not a narcotic. The MHLW's 8 September 2021 notice identifies CLONAZOLAM among the three substances newly designated as psychotropics, effective 8 October 2021; handling is regulated under the Narcotics and Psychotropics Control Act, so the requested narcotic-designation correction is not supported.

PhilippinesIllegalDangerous drug

Dangerous Drugs Board Regulation No. 6, series of 2022²²²³²⁴

The Philippine Dangerous Drugs Board’s current regulations index lists this exact regulation as ‘Inclusion of Clonazolam in the list of Dangerous Drugs.’ The underlying statute treats unauthorized importation, sale, and possession of dangerous drugs as unlawful, so this is a direct identity-specific dangerous-drug control rather than an inference from clonazepam or a benzodiazepine class rule.

PortugalRestrictedTabela IV

Lei n.º 9/2023, de 3 de março, artigo 5.º e Tabela IV anexa ao Decreto-Lei n.º 15/93²⁷

Portugal's official gazette expressly adds clonazolam, identified as 6-(2-Clorofenil)-1-metil-8-nitro-4H-[1,2,4]triazolo[4,3-a][1,4]benzodiazepina, to Tabela IV of Decreto-Lei n.º 15/93. This is exact-name and exact-structure evidence, not an inference from clonazepam or a benzodiazepine class.

SingaporeRestrictedPsychoactive substance

Misuse of Drugs Act 1973, ss. 2 and 11F–11I^29303132

Clonazolam is not named in the current First Schedule, and the Schedule's listed Class C benzodiazepines (nimetazepam, flunitrazepam and triazolam) do not create a general benzodiazepine-derivative rule. However, clonazolam's CNS-depressant activity brings it within the Act's functional definition of a psychoactive substance; absent an Act authorisation, manufacture, trafficking, import/export, possession and consumption are offences. The Act provides a defence for specified conduct undertaken for a legitimate purpose other than human consumption.

SpainRestrictedLista IV de sustancias psicotrópicas

Orden SND/1248/2021, de 5 de noviembre, que modifica el anexo 1 del Real Decreto 2829/1977 (texto consolidado vigente)³⁵³⁶

Clonazolam is expressly named, with its chemical designation, in List IV of Annex 1. Spain's current consolidated Real Decreto 2829/1977 subjects List IV substances to controlled manufacture, trade, import/export, and pharmacy dispensing; pharmacy dispensing of a substance itself is only on a magistral-formula prescription, while preparations containing it require a medical prescription. The order also states that no medicines containing these newly listed substances were authorized in Spain at the time of enactment.

SwitzerlandVerzeichnis ECitation needed

Specifically named as a controlled substance under Verzeichnis E (List E) of Swiss narcotics legislation.

AustraliaRestrictedNarcotic import/export controls

Office of Drug Control controlled-substances entry (Commonwealth import/export controls)¹

The current ODC entry for clonazolam requires an import licence and permit and an export licence and permit. This settles Commonwealth import/export controls only; it does not establish a nationwide rule for domestic possession, supply, manufacture, or use, and does not rely on the expired June 2024 Poisons Standard.

BrazilRestrictedLista B1 psychotropic substance

Portaria SVS/MS nº 344/1998, Anexo I, Lista B1, as updated by RDC Anvisa nº 581/2021⁴⁵⁶

Clonazolam is expressly named (not inferred from clonazepam or a class rule) in Lista B1. The current official ANVISA controlled-substances page identifies the list as the updated annex to Portaria 344/1998 and records RDC 581/2021's inclusion of Clonazolam in B1. Under Portaria 344/1998, substances in B1 are psychotropics subject to special control, including special authorization for listed-substance activities and prescription-notification requirements for dispensing medicines containing B1 substances.

Czech RepublicIllegalKlonazolam

Government Regulation No. 463/2013 Coll., on lists of addictive substances; Act No. 167/1998 Coll., on addictive substances⁸⁹

Controlled under § 1, d), 2. of Nařízení vlády č. 463/2013 Sb. Use is restricted exclusively to limited research purposes or very limited therapeutic applications.

GermanyRestrictedBtMG Anlage II

Betäubungsmittelgesetz (BtMG), Anlage II; §§ 1(1), 3(1), 29(1) nos. 1 and 3^12131415

Clonazolam is expressly listed in the current BtMG Anlage II (rather than merely covered by an analogue/group rule). Anlage II is the schedule of traffic-capable but non-prescribable narcotics. BtMG § 3(1) requires BfArM permission for manufacture, trade, import, export, supply, sale/other placing on the market, and acquisition. BtMG § 29(1) criminalizes unauthorized listed conduct and possession without written acquisition permission (up to five years' imprisonment or a fine, subject to the statute's terms). The allowed canonical replacement is restricted_other because the exact substance is subject to a controlled, permission-based Schedule II regime, not an unqualified prohibition.

ItalyIllegalTabella IV

Decreto 6 agosto 2021, Aggiornamento delle tabelle contenenti l'indicazione delle sostanze stupefacenti e psicotrope¹⁷¹⁸

The official decree expressly adds exact clonazolam to Table IV of DPR 309/1990 (not Table I); it entered into force 15 days after publication. The Ministry states that Tables I–IV are nationally/internationally controlled substances and are updated as needed.

NetherlandsIllegalList II

Opiumwet, List II²¹

Controlled as a List 2 substance under the Opium Law. Possession, production, and distribution are illegal.

PolandRestrictedPsychotropic group IV-P

Rozporządzenie Ministra Zdrowia z dnia 17 sierpnia 2018 r. w sprawie wykazu substancji psychotropowych, środków odurzających oraz nowych substancji psychoaktywnych, tekst jednolity: Dz.U. 2024 poz. 1139, załącznik nr 1, grupa IV-P, poz. 76; read with the Act of 29 July 2005 on Counteracting Drug Addiction (Dz.U. 2023 poz. 1939), arts. 33–37 and 53–62.²⁵²⁶

This is an exact named listing, not an analogue inference. IV-P substances may be used only for medical, industrial, or research purposes (Act art. 33(1)); possession is limited to persons authorized under the Act (art. 34(1)). Manufacture, processing, alteration, import, distribution, wholesale trade, and cross-border movements are subject to the Act's authorizations/permits (arts. 35, 37, 40); unauthorized possession and specified unauthorized conduct carry criminal penalties (arts. 53, 55, 56, 62). The appropriate controlled-substance classification is restricted_other rather than prescription_only because the legal listing controls the substance directly and the Act permits specified non-prescription industrial and research uses subject to authorization.

RussiaIllegalList I

Government Resolution No. 681 of 30 June 1998 (current text), as amended by Government Resolution No. 827 of 12 July 2017²⁸

Clonazolam (Клоназолам) is expressly listed in List I of the current controlled-substances schedules established by Resolution No. 681. List I placement is prohibitory; it is not Schedule/List III.

South KoreaRestrictedAppendix 6 item 77: Clonazolam

Narcotics Control Act Enforcement Decree, Appendix 6; Narcotics Control Act arts. 2(3)(d), 4³³³⁴

Clonazolam is expressly listed as a psychotropic drug in Appendix 6, the schedule for Article 2(3)(d) substances. Handling is prohibited for persons who are not authorized narcotics handlers, subject to statutory exceptions; this is a controlled-status finding rather than an unqualified blanket-prohibition finding.

SwedenHazardous SubstanceCitation needed

Classified as an addictive substance following a recommendation by Sweden's public health agency on June 1, 2015. Production, import, trading, and possession require special authorization.

United KingdomIllegalClass C / Schedule 1

Misuse of Drugs Act 1971, Schedule 2 Part III; Misuse of Drugs Regulations 2001, Schedule 1^37383940

Classified as a Class C drug under the May 2017 amendment to the Misuse of Drugs Act 1971, alongside several other designer benzodiazepines. Possession, production, and supply are criminal offenses.

References

Citations

Automated synthesis
Information aggregated and synthesized using an autonomous workflow built by Josie Kins.

Suggest an edit

Spotted a mistake, an outdated claim, or something missing from the Clonazolam article? Send the editors a private note. Feedback lands in a moderation queue and is never shown on the site.

Wish to give generalised feedback? You can do so here.

Not yet reviewed — this article is pending editorial review by Lyrea.

Clonazolam

Psychoactive Class

Depressant Sedative Anxiolytic GABAergic Muscle Relaxant

Chemical Class

Triazolobenzodiazepine

Dosage & Duration

Dosage

Threshold~50 µg

Light50-200 µg

Moderate200-400 µg

Strong400-500 µg

Heavy500+ µg

Duration

Onset10-30 minutes

After Effects1-12 hours

Total6-10 hours

Subjective Effects

Effects vary widely by individual, dose, and context.

Physical

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

Respiratory depression Dizziness Muscle relaxation Motor control loss

Cognitive

Amnesia Anxiety suppression Thought deceleration Disinhibition Information processing suppression Euphoria Compulsive redosing

Forked from Subjective Effect Documentation

by Josie KinsSeptember 2015.

Reagent Testing

Expected colorimetric results for common reagent tests. Colors show reaction change over 1–2 minutes.

Zimm(ZI)

Marquis(MQ)

No reaction

Mecke(ME)

No reaction

Mandelin(MD)

No reaction

PROtestkit.eu

Pharmacology

Pharmacodynamics

Pharmacokinetics

Interactions

Interactions not written up yet

An unlisted combination is an unknown one, not a safe one. Check a dedicated combination chart before mixing.

Check

TripSit

Tolerance

Full Tolerance

Cross Tolerance

Benzodiazepines

Baseline Reset

Harm Potential

Addiction & Dependence

Psychological

Extremely High

Physical

Extremely High

Psychosis Risk

Seizure Risk

History & Culture

Legality

International

By Country

United StatesIllegalSchedule I

DEA's final rule, effective April 1, 2026, permanently placed clonazolam in Schedule I. It supersedes the prior temporary Schedule I placement and extension through July 26, 2026.

By state

IowaIllegalSchedule I clonazolam

KansasIllegalSchedule I ACSCN 2786

MarylandIllegalSchedule I incorporation

MinnesotaIllegalSchedule I depressant

NebraskaIllegalSchedule I depressant

NevadaIllegalSchedule I

New MexicoIllegalSchedule I depressant (benzodiazepine)

North CarolinaIllegalSchedule I systemic depressant

North DakotaIllegalSchedule I depressant

OregonIllegalState controlled substance listing

AustriaRestrictedPsychotropic substance

Psychotropenverordnung (PV), Anlage 1, Z 2; §§ 1–2²³

CanadaRestrictedSchedule IV benzodiazepine

Controlled Drugs and Substances Act, Schedule IV, item 18⁷

DenmarkIllegalEuphoric substance — list E

Bekendtgørelse om euforiserende stoffer, BEK nr 405 af 26/03/2026, Bilag 1, liste E, nr. 18; §§ 3 and 6¹⁰¹¹

IrelandIllegalControlled drug

Misuse of Drugs Act 1977 (Controlled Drugs) (Declaration) Order 2022, S.I. No. 176/2022¹⁶

JapanIllegalPsychotropic (向精神薬)

PhilippinesIllegalDangerous drug

Dangerous Drugs Board Regulation No. 6, series of 2022²²²³²⁴

PortugalRestrictedTabela IV

Lei n.º 9/2023, de 3 de março, artigo 5.º e Tabela IV anexa ao Decreto-Lei n.º 15/93²⁷

SingaporeRestrictedPsychoactive substance

Misuse of Drugs Act 1973, ss. 2 and 11F–11I^29303132

SpainRestrictedLista IV de sustancias psicotrópicas

Orden SND/1248/2021, de 5 de noviembre, que modifica el anexo 1 del Real Decreto 2829/1977 (texto consolidado vigente)³⁵³⁶

SwitzerlandVerzeichnis ECitation needed

Specifically named as a controlled substance under Verzeichnis E (List E) of Swiss narcotics legislation.

AustraliaRestrictedNarcotic import/export controls

Office of Drug Control controlled-substances entry (Commonwealth import/export controls)¹

BrazilRestrictedLista B1 psychotropic substance

Portaria SVS/MS nº 344/1998, Anexo I, Lista B1, as updated by RDC Anvisa nº 581/2021⁴⁵⁶

Czech RepublicIllegalKlonazolam

Government Regulation No. 463/2013 Coll., on lists of addictive substances; Act No. 167/1998 Coll., on addictive substances⁸⁹

Controlled under § 1, d), 2. of Nařízení vlády č. 463/2013 Sb. Use is restricted exclusively to limited research purposes or very limited therapeutic applications.

GermanyRestrictedBtMG Anlage II

Betäubungsmittelgesetz (BtMG), Anlage II; §§ 1(1), 3(1), 29(1) nos. 1 and 3^12131415

ItalyIllegalTabella IV

Decreto 6 agosto 2021, Aggiornamento delle tabelle contenenti l'indicazione delle sostanze stupefacenti e psicotrope¹⁷¹⁸

NetherlandsIllegalList II

Opiumwet, List II²¹

Controlled as a List 2 substance under the Opium Law. Possession, production, and distribution are illegal.

PolandRestrictedPsychotropic group IV-P

RussiaIllegalList I

Government Resolution No. 681 of 30 June 1998 (current text), as amended by Government Resolution No. 827 of 12 July 2017²⁸

South KoreaRestrictedAppendix 6 item 77: Clonazolam

Narcotics Control Act Enforcement Decree, Appendix 6; Narcotics Control Act arts. 2(3)(d), 4³³³⁴

SwedenHazardous SubstanceCitation needed

Classified as an addictive substance following a recommendation by Sweden's public health agency on June 1, 2015. Production, import, trading, and possession require special authorization.

United KingdomIllegalClass C / Schedule 1

Misuse of Drugs Act 1971, Schedule 2 Part III; Misuse of Drugs Regulations 2001, Schedule 1^37383940

Classified as a Class C drug under the May 2017 amendment to the Misuse of Drugs Act 1971, alongside several other designer benzodiazepines. Possession, production, and supply are criminal offenses.

References

Citations

Automated synthesis
Information aggregated and synthesized using an autonomous workflow built by Josie Kins.

Suggest an edit

Spotted a mistake, an outdated claim, or something missing from the Clonazolam article? Send the editors a private note. Feedback lands in a moderation queue and is never shown on the site.

Wish to give generalised feedback? You can do so here.