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Temazepam

Overview

Temazepam is a synthetic depressant of the benzodiazepine class. It is the 3-hydroxy derivative of diazepam, metabolizing more cleanly than most benzodiazepines with fewer long-lasting active breakdown products.[1] It amplifies GABA — the brain's main inhibitory signaling system — slowing neural activity to produce sedation and sleep.[2]

Temazepam is a synthetic depressant of the benzodiazepine class. It is the 3-hydroxy derivative of diazepam, distinguished by simpler metabolism and fewer active metabolites.[1] Temazepam is a non-selective positive allosteric modulator of GABA-A receptors, producing its effects by amplifying the brain's primary inhibitory signaling system.[2]

Entity
Temazepam
PSX-0347
Temazepam 2D chemical structure
Open Beta

Psychedex is in open beta. We are still fine-tuning the generation and review process. Please double-check sources.

NoticeAll →
•Dangerous withdrawal, taper carefully
•High dependence, taper carefully
•1 lethal interaction(all →)
Common namesTemazepam, Restoril, Normison
Substitutive namehydroxydiazepam
Threshold
< 2 mg
Light
5 – 10 mg
Common
10 – 30 mg
Strong
30 – 40 mg
Heavy
40+ mg
Bioavailability:90 – 96%
12340 h2 h4 h6 h
1Onset
30m–1h2Peak
1h–1.5h3Plateau
1.5h–2.5h4Resolution
1h–2hAftereffects2h–5h
Total7h–8h
Buildupmoderate
Full reset10.5 days
Cross-tol.
benzodiazepines, barbiturates, zolpidem +3 more
Absolute4 entries
Known benzodiazepine hypersensitivityPregnancyAcute narrow-angle glaucomaInjection by any route
Relative7 entries
Obstructive sleep apneaMyasthenia gravisSevere depression with suicidal ideationHistory of substance use disorderSevere hepatic impairmentElderly patientsAcute alcohol intoxication
Dosage varies by body weight, tolerance & metabolism · Not medical advice · Terms
See an error? Suggest correction
See an error? Suggest correction

Synthesized in 1964 at Hoffmann-La Roche, temazepam received FDA approval in 1981 for short-term insomnia. Its gel capsule form became widely injected in the UK and Australia — temazepam is nearly insoluble in water, and injected material solidified in blood vessels, causing gangrene and amputation.[3][4] Gel capsules were permanently withdrawn; temazepam is now available only as tablets, classified as a Schedule IV controlled substance internationally.

Subjective effects include sedation, anxiety relief, muscle relaxation, and anterograde amnesia — impaired ability to form new memories while the drug is active. The experience is one of gradual, enveloping heaviness: a warm cognitive dimming and physical loosening that builds steadily toward sleep. Morning-after grogginess, memory gaps for events during peak effect, and slowed coordination are characteristic unwanted effects.

Temazepam produces physical dependence with regular use, and tolerance to its sleep-promoting effect builds within two to three weeks of nightly dosing.[5][6] Alone, it is rarely fatal — but combining it with opioids or alcohol dramatically raises the risk of fatal stopped breathing.[7] Decades of clinical use have produced a well-characterized safety profile, though substance-specific lethal dose values remain unpublished.

History[edit]

Discovery

Temazepam was synthesized in 1964 at Hoffmann-La Roche — the same laboratory behind diazepam and nitrazepam. It is a deliberate structural modification of diazepam, designed to metabolize more simply.[1] The first studies of how it moves through the body were published in 1977, confirming that the soft gel capsule form was absorbed significantly faster than hard capsules.[8][9]

Clinical adoption and the gel capsule crisis

By the mid-1980s, gel capsules of temazepam were widely injected in Scotland. Temazepam is nearly insoluble in water; injected gel solidified at body temperature, blocking blood vessels and causing gangrene and amputation.[3][4][10] Glasgow and Edinburgh saw sharp rises in drug-related deaths between 1990 and 1992, with temazepam — often combined with heroin — identified as a major factor.[11]

Modern era

The UK withdrew gel capsules in 1996; Australia followed in 2004.[3] Temazepam remains available only as tablets, positioned as second-line treatment for insomnia after behavioral therapy.[12][13] A recent clinical trial has evaluated temazepam for insomnia in advanced cancer patients.[14]

Chemistry[edit]

Temazepam belongs to the 1,4-benzodiazepine family, classified as a 3-hydroxybenzodiazepinone. It is the 3-hydroxy, N1-methyl derivative of diazepam — meaning it is one of diazepam's own metabolites, formed in the liver after diazepam is taken. Its molecular formula is C₁₆H₁₃ClN₂O₂ (molecular weight 300.74 g/mol).

Temazepam's own metabolism produces oxazepam — a further breakdown product that is itself an active benzodiazepine.[15] The compound is nearly insoluble in water.[16] This physical property explains the catastrophic injuries associated with injecting it — the material solidifies at body temperature inside blood vessels.[3]

Pharmacology[edit]

Mechanism of action

Temazepam binds to GABA-A receptors — the brain's primary inhibitory receptors — and amplifies the effect of GABA, the neurotransmitter that quiets neural activity.[2] When GABA activates a receptor, temazepam increases the flow of chloride ions into the neuron, making it harder to fire. The result is widespread slowing of brain activity: sedation, anxiety relief, muscle relaxation, memory suppression, and anticonvulsant effect.

Unlike newer sleep medications such as zolpidem and zaleplon, which target a specific receptor variant, temazepam acts across multiple GABA-A receptor types.[17] This broader action produces a wider profile — more pronounced muscle relaxation and greater memory impairment than Z-drugs at comparable sleep-promoting doses. No substance-specific binding affinity values have been published.citation needed

Pharmacokinetics

Temazepam is well absorbed by mouth, with peak blood levels in 1–2 hours and a half-life of 3.5 to 18.4 hours.[2] Unlike most benzodiazepines, it is broken down through a direct conjugation pathway rather than the liver's CYP450 enzyme system.[15][2] This means the metabolic drug interactions that complicate other benzodiazepines like alprazolam and diazepam largely do not apply.[1]

Neuroscience[edit]

Where it acts

Temazepam amplifies inhibitory GABA signaling across multiple brain regions simultaneously. In the thalamus and cortex, this suppresses arousal signals and facilitates sleep onset.[2] In the amygdala and connected structures, the same mechanism reduces anxiety.[18][19]

In the hippocampus, temazepam disrupts the process by which new memories form.[18] This produces the dose-dependent anterograde amnesia that is one of the drug's defining features.

Tolerance and reward

With repeated use, GABA-A receptors adapt by reducing their sensitivity to temazepam's effect — producing the tolerance documented within 2–3 weeks of nightly use.[5] Temazepam also indirectly activates dopamine reward circuits by reducing inhibition on dopamine-producing neurons, driving the reinforcement that underlies compulsive use.citation needed

Subjective Effects[edit]

Summary

Temazepam produces a gradual, enveloping sedation that spreads through the mind and body together. It begins as tension dissolving — mental quiet and physical loosening — then deepens into full-body heaviness and cognitive fog as the effect takes hold.

Compared to diazepam, temazepam clears more predictably with less next-day residual heaviness. Against zolpidem, it produces more pronounced muscle relaxation and memory suppression — the broader profile of a non-selective benzodiazepine acting across multiple receptor types.

Synthesized in 1964 at Hoffmann-La Roche, temazepam received FDA approval in 1981 and is prescribed primarily for short-term insomnia. Its gel capsule formulation drove a major injection misuse crisis in the United Kingdom and Australia — injected gel solidified in blood vessels, causing gangrene and amputation.[3][4] Capsule formulations were permanently withdrawn; temazepam remains available only as tablets, classified as Schedule IV internationally.

Subjective effects include sedation, anxiolysis, muscle relaxation, and anterograde amnesia. The experience is one of gradual, enveloping heaviness — a warm cognitive dimming and physical loosening that builds steadily toward sleep, with a broader bodily weight than the targeted sedation of newer sleep medications. Morning-after grogginess, memory gaps for events during peak effect, and psychomotor impairment are characteristic unsought effects.

Temazepam produces physical dependence with regular use, and while rarely fatal alone, its lethality increases substantially when combined with opioids or alcohol.[5] Tolerance to the sleep-promoting effect develops within two to three weeks of nightly use,[6] driving dose escalation that deepens dependence without restoring efficacy.[7] Decades of clinical use provide a well-characterized safety profile, though substance-specific lethal dose values and receptor binding affinities remain unpublished.

History[edit]

Discovery

Temazepam was synthesized in 1964 at Hoffmann-La Roche, the laboratory that produced chlordiazepoxide, diazepam, and nitrazepam. Structurally, it is the 3-hydroxy, N1-methyl derivative of diazepam — a deliberate modification that routes metabolism through a simpler conjugation pathway rather than the oxidative processing required by its parent compound.[1] The first human pharmacokinetic studies, published in 1977, characterized plasma profiles following oral administration of soft gelatin capsules and confirmed that the soft gel formulation produced significantly faster absorption than hard capsules.[8][9]

Clinical adoption and the gel capsule crisis

Temazepam was marketed in the United Kingdom as Normison and Euhypnos, and received FDA approval in 1981 as Restoril in the United States. By the mid-1980s, its gel capsules had become widely injected in Scotland — users heated the capsules to liquefy the contents for intravenous use. The consequences were catastrophic: temazepam is nearly insoluble in water, and injected gel solidified at body temperature, causing vascular blockage, gangrene, and amputation.[3][4][10] Glasgow and Edinburgh saw sharp increases in drug-related deaths during 1990–1992, with temazepam — frequently combined with heroin — identified as a major contributor.[11]

Modern era

The UK withdrew gel capsules in 1996; Australia followed in 2004.[3] Temazepam remains available only as tablets, positioned by clinical guidelines as second-line pharmacotherapy for insomnia after cognitive behavioral therapy.[12][13] Recent clinical investigation includes a Phase III trial evaluating temazepam for insomnia in advanced cancer patients.[14]

Chemistry[edit]

Structural class

Temazepam belongs to the 1,4-benzodiazepine family, classified specifically as a 3-hydroxybenzodiazepinone. The 3-hydroxy group at C-3 and the N1-methyl substituent distinguish it from its parent compound diazepam, of which it is a direct metabolite. The 7-chloro and 5-phenyl substituents are conserved features shared with diazepam, oxazepam, and several other clinical benzodiazepines.

Temazepam's structural relationship to oxazepam is particularly close: oxazepam is temazepam's own N-desmethyl metabolite, produced by minor oxidative demethylation.[15]

Molecular identity

Molecular formulaC₁₆H₁₃ClN₂O₂
Molecular weight300.74 g/mol

The core structure consists of a 1,4-benzodiazepine ring fused to a chloro-substituted benzene ring at position 7, with a phenyl group at position 5, a methyl on the N1 nitrogen, a carbonyl at C-2, and a hydroxyl at C-3.

Stereochemistry

The hydroxyl group at C-3 creates a chirality center, and pharmaceutical preparations contain both (R)- and (S)-enantiomers as a racemic mixture. Whether one enantiomer preferentially contributes to the hypnotic, anxiolytic, or amnestic effects has not been determined.citation needed

Physical properties

Temazepam is a white to slightly yellow crystalline powder, freely soluble in chloroform but very slightly soluble in water. This near-insolubility in water is directly relevant to its injury profile: when gel capsule contents were injected intravenous, the compound solidified at body temperature, causing mechanical vascular blockage on top of direct chemical damage to blood vessel walls.[3][16]

Pharmacology[edit]

Mechanism of action

Temazepam binds at the benzodiazepine site on GABA-A receptors — the brain's primary inhibitory receptor — and amplifies the effect of the neurotransmitter GABA. When GABA binds the receptor, temazepam increases the flow of chloride ions into the neuron, making it harder to fire. The resulting widespread reduction in neural activity produces sedation, anxiety relief, muscle relaxation, memory suppression, and anticonvulsant effects.[2]

Unlike newer sleep medications such as zolpidem and zaleplon, which target a specific receptor subtype, temazepam acts broadly across multiple GABA-A receptor variants. This non-selective binding accounts for its combined hypnotic, anxiolytic, muscle-relaxant, and amnestic properties — a broader pharmacological profile than the Z-drug class.[17]

No substance-specific binding affinity values have been published for temazepam; its pharmacological characterization relies on class-level properties of non-selective benzodiazepines.citation needed

Pharmacokinetics

Temazepam is well absorbed orally with high bioavailability, as very little is lost to first-pass liver processing (approximately 8%).[2] Peak blood levels are reached within 1–2 hours with current tablet formulations. The half-life ranges from 3.5 to 18.4 hours (mean 8.8 hours), and the compound is approximately 96% bound to plasma proteins.[2]

The key metabolic distinction of temazepam is its primary elimination through direct glucuronide conjugation — a Phase II pathway — rather than the CYP450-dependent oxidation used by most benzodiazepines.[15][2] The resulting glucuronide metabolite is inactive and excreted by the kidneys (80–90% of the dose). A minor pathway produces oxazepam, itself an active benzodiazepine.[15]

This conjugation-first metabolism means temazepam largely avoids the drug-drug interactions that complicate therapy with CYP-dependent benzodiazepines like diazepam, alprazolam, and triazolam.[1] In elderly patients, conjugative metabolism remains relatively stable, but increased brain sensitivity to the drug produces stronger sedation at any given blood level.[1]

Neuroscience[edit]

Where it acts

Temazepam's effects arise from amplifying inhibitory GABA signaling across multiple brain regions simultaneously. In the thalamus and cortex, potentiation of GABA-A receptors containing α1 subunits suppresses arousal signals and facilitates sleep onset.[2] In the amygdala and limbic structures, α2-containing receptors mediate anxiety reduction.[18][19]

In the hippocampus, α5-containing receptors disrupt memory encoding, producing the dose-dependent anterograde amnesia that defines much of the temazepam experience.[18] Spinal cord and brainstem receptors containing α2 and α3 subunits reduce motor neuron excitability, accounting for the muscle-relaxant effect.

Tolerance and reward

Repeated use triggers adaptive changes at GABA-A receptors — receptor internalization, altered subunit expression, and uncoupling of the allosteric mechanism — producing the hypnotic tolerance documented within 2–3 weeks of nightly use.[6] The mesolimbic pathway involves indirect disinhibition of dopamine neurons: temazepam potentiates GABA-A receptors on inhibitory interneurons in the ventral tegmental area, releasing dopamine neurons from their normal braking, and driving the reinforcement that underlies compulsive use.citation needed

Subjective Effects[edit]

Summary

The temazepam experience is defined by a gradual, enveloping sedation that spreads from anxiolysis into full-body heaviness and cognitive dimming. At lower doses, the effect is primarily one of tension relief — mental chatter quiets, muscles loosen, and the transition toward sleep feels natural rather than forced. At higher doses, the sedation deepens into pronounced mental fog, motor coordination deteriorates, and anterograde amnesia becomes a dominant feature: events during peak effect may be partially or entirely absent from later recall.

Compared to diazepam, temazepam offers similar anxiety relief with more predictable clearance and less next-day carryover from active metabolites. Against zolpidem, temazepam's non-selective receptor profile produces more pronounced muscle relaxation and a heavier subjective weight, with greater amnestic burden at equivalent sleep-promoting doses.

Effect Grid

Dose Level:
Description

The standard clinical dose range, producing progressive sedation, clear anxiety suppression, and definite muscle relaxation. Thought deceleration is prominent — cognitive processing slows noticeably. Anterograde amnesia becomes dose-dependent and clinically significant: events occurring during peak effect may be incompletely recalled or entirely absent from later memory. Emotional suppression deepens, and disinhibition may emerge.

Physically, bodily heaviness is pronounced and motor control impairment is measurable. Sleep induction becomes the dominant effect at the upper end of this range. Morning-after psychomotor impairment and memory fog are documented, particularly above 15 mg and in elderly patients.

The 15 mg and 20 mg doses are the most commonly studied in clinical trials. At 30 mg (upper bound), cognitive euphoria may be noted alongside significant functional impairment. Delusions of sobriety — the subjective belief of normal functioning while objectively impaired — become relevant at this level.

Modeled from the effect's dose-dependence curve — not per-substance measurements.

Perception(7)likelihood · intensity
Dreaming suppression
likely
Proprioceptive distortion
possible
Spatial disorientation
possible
Visual acuity suppression
possible
Vestibular distortion
possible
Double vision!
rare
Visual processing suppression
rare

Vestibular distortion · Visual processing suppression

Body(17)likelihood · intensity
Sedation
likely
Muscle relaxation
likely
Motor control impairment!
likely
Bodily heaviness
likely
Physical fatigue
likely
Dizziness
possible
Body high
possible
Respiratory depression!
possible
Abnormal heartbeat!
rare

Physical fatigue · Dizziness · Body high · Breathing alteration · Tactile euphoria · Dry mouth · Nystagmus (eye wobbles) · Headache · Laughter fits · Nausea · Pain suppression · Abnormal heartbeat

Breathing alteration · Tactile euphoria · Dry mouth · Nystagmus (eye wobbles) · Headache · Laughter fits · Nausea · Pain suppression

Thinking(20)likelihood · intensity
Analysis suppression
likely
Cognitive impairment
likely
Decision impairment!
likely
Focus suppression
likely
Thought deceleration
possible
Language suppression
possible
Memory suppression
possible
Delusions of sobriety!
possible
Suggestibility enhancement!
possible

Thought deceleration · Language suppression · Memory suppression · Cognitive fatigue · Information processing suppression · Motivation suppression · Memory fragmentation · Cognitive euphoria · Confusion · Suggestibility enhancement · Thought disorganization · Compulsive redosing urge · Humor enhancement · Amnesia · Delirium

Cognitive fatigue · Information processing suppression · Motivation suppression · Memory fragmentation · Cognitive euphoria · Confusion · Thought disorganization · Compulsive redosing urge · Humor enhancement · Amnesia · Delirium

Feeling(8)likelihood · intensity
Anxiety suppression
likely
Emotional suppression
possible
Euphoria
possible
Emotional lability
possible
Depression!
rare
Dysphoria
rare
Irritability
rare
Paranoia!
rare

Emotional lability · Dysphoria · Irritability

Self(10)likelihood · intensity
Disinhibition
possible
Communication suppression
possible
Emotional susceptibility
possible
Sociability enhancement
possible
Automaticity
possible
Craving
possible
Depersonalization
rare
Derealization
rare
Self-control suppression!
rare

Automaticity · Craving · Depersonalization · Derealization · Cognitive disconnection

Cognitive disconnection

Time(2)likelihood · intensity
Temporal disorientation
possible
Time alteration
possible
Awareness(1)likelihood · intensity
Reality testing impairment!
rare
report missing effect
Likelihood: how common this effect is at the selected dose level.This effect has safety implications — review before use.

Timeline

Safety[edit]

Harm
Acute toxicity
Low
Chronic toxicity
Moderate
Withdrawal
Severe
Tolerance buildup
moderate
Tolerance reset
10.5 days
Dependence
Physical
High
Psychological
Moderate
Compulsive redosing
Moderate
Dose escalation
Moderate
Cross-tol.
benzodiazepines · barbiturates · zolpidem
Risk Shape
TOXPHYPSYWDRREDTOL

Toxicity

Acute toxicity

Temazepam overdose causes excessive sedation, confusion, impaired coordination, slowed breathing, and in severe cases, coma.[2] Temazepam alone is rarely fatal; nearly all deaths involve co-ingestion with opioids or alcohol, which combine to suppress breathing beyond what either substance causes alone.[7]

StatPearls states temazepam is "approximately 10 times more hazardous than diazepam" in overdose;[2] this claim could not be traced to a primary source.safety citation needed No published lethal dose data exist for temazepam.safety citation needed

Injection toxicity

Temazepam must never be injected by any route. It is nearly insoluble in water and directly damages blood vessel walls.[3] Injected material solidifies at body temperature, causing mechanical blockage on top of chemical injury. Every patient in clinical case series who injected temazepam into an artery suffered severe tissue death; injection into the radial artery invariably required amputation.[4][10] Documented complications include abscesses, skin ulceration, nerve damage, blood clots, gangrene, and muscle breakdown.[2][3]

Respiratory effects

Benzodiazepines relax the muscles that keep the airway open, making temazepam contraindicated in obstructive sleep apnea. In patients with stable COPD, a 10 mg dose did not significantly impair breathing or gas exchange.[21] Respiratory depression remains the primary mechanism of death in polydrug overdose.

Pregnancy

Temazepam carries FDA pregnancy Category X designation. Animal studies documented birth defects including skull malformations and rib abnormalities. Benzodiazepine exposure during pregnancy is associated with neonatal withdrawal — low muscle tone, breathing difficulties, and low body temperature in the newborn.[2]

Elderly

Falls are the primary safety concern in older adults taking temazepam. It impairs balance and standing steadiness,[22] and carries similar hip fracture risk to triazolam.[23] A meta-analysis of 24 trials found harmful cognitive effects nearly 5 times more common with sedative-hypnotics than placebo in older adults.[24]

Overdose management

Standard management is supportive: maintain the airway and monitor vital signs. Flumazenil can reverse benzodiazepine effects but is not recommended for routine overdose management — a meta-analysis found significantly more adverse events with flumazenil than placebo, including dangerous heart rhythm changes and seizures.[25]

Psychological risks

Temazepam produces dose-dependent anterograde amnesia — impaired ability to form new memories during the period of drug activity.[18] At therapeutic doses this appears as difficulty recalling events after ingestion; at higher doses, complete memory gaps may occur.

Rare paradoxical reactions — agitation, aggression, paranoia — are a recognized class effect, more common in elderly patients and those with pre-existing psychiatric conditions.[2] Delusions of sobriety — the belief of functioning normally while objectively impaired — may drive dose escalation. Rebound insomnia affects 26–58% of users following discontinuation of temazepam 20 mg,[26] often accompanied by mood disturbance.[5] Vivid dreams and nightmares are also reported during use.[2]

Tolerance & dependence

Tolerance to temazepam's sleep-promoting effect develops with continued use. Controlled studies demonstrated significant tolerance within 14–22 nights of nightly dosing,[5] though a 3-month trial (n=175) found some patients maintained efficacy at 30 mg without tolerance.[20] Cross-tolerance exists with all benzodiazepines and GABA modulators.[27]

Physical dependence develops with regular use. Stopping produces withdrawal: rebound effect insomnia, anxiety, tremor, sensory disturbances, and autonomic instability; rarely, seizures and delirium occur.[6][27] Onset is typically 1–3 days after the last dose; duration is weeks, with some patients experiencing protracted symptoms lasting months.

1LETHAL
21DANGEROUS
26CAUTION
12UNGRADED
60 rules0 SOURCE-VERIFIED1 EDITOR-REVIEWED

Temazepam bypasses the liver's CYP450 enzyme system,[2][1] so the metabolic drug interactions that complicate other benzodiazepines largely do not apply. Its interaction risk is additive depression: combining it with any sedating substance amplifies breathing suppression.

Combining with opioids produces additive respiratory depression and is a leading cause of drug-related death;[7] the FDA has issued a boxed warning against concurrent benzodiazepine-opioid prescribing.[2] Alcohol, barbiturates, sedating antihistamines, and antipsychotics all carry additive depressant risk.[2][7] Monoamine oxidase inhibitors are listed as moderate interactants, though the precise mechanism is not fully characterized.[2]

Contraindications

11 known
4ABSOLUTE
7RELATIVE

Absolute contraindications:

  • Pregnancy (FDA Category X): Documented birth defects in animal studies and neonatal withdrawal[2]
  • Known hypersensitivity to temazepam or other benzodiazepines[2]
  • Acute narrow-angle glaucomacitation needed

Relative contraindications:

  • Obstructive sleep apnea: muscle relaxation may worsen airway collapse
  • Severe liver disease: Severe impairment may affect all metabolic pathways
  • Myasthenia gravis: Muscle-relaxant effects may worsen neuromuscular weakness[2]
  • Acute alcohol intoxication: Additive depressant risk[2]
  • Severe depression with suicidal thoughts: Depressant effects and disinhibition may increase suicide risk[2]
  • History of substance use disorder: Elevated misuse and dependence risk[6]
  • Elderly patients: Increased sensitivity and fall risk[1][24]

Harm Reduction[edit]

Forms & Identification

Reagent ResultsNot recorded+ add reagent results
AppearanceNot recorded+ add appearance
Red FlagsNot recorded+ add red flags

The main identification concern with temazepam isn't adulteration of genuine pharmacy stock. It is verifying that tablets obtained outside a pharmacy are actually temazepam and not a counterfeit containing a more potent benzodiazepine or other active compound.

Reagent testing does not reliably distinguish between different benzodiazepines. Pill identification databases matching imprint codes are the most practical verification method for pharmaceutical tablets.

Guidelines

  • Take only the prescribed dose. Higher doses intensify amnesia and psychomotor impairment without proportionally improving sleep.
  • Take temazepam immediately before getting into bed. Walking, socializing, or using a phone after dosing increases the likelihood of amnestic behavior and impaired decisions.
  • Allow a full 7–8 hours for sleep. Taking temazepam without sufficient sleep time increases morning-after impairment.
  • Do not drive or operate machinery the morning after use until certain that alertness has fully returned.
  • Do not use nightly for more than 2–3 weeks without medical review. Tolerance to the sleep-promoting effect develops within this window, and physical dependence begins.
  • Never crush, dissolve, or inject tablets. Injection of temazepam in any form causes severe vascular injury.

Set & Setting

Temazepam is a sedative-hypnotic taken at bedtime. The environment should support safe sleep — a secure location where driving, operating machinery, or making important decisions is not necessary. Because temazepam impairs memory formation, anything requiring recall — conversations, commitments, financial decisions — should be completed before dosing.

The amnestic and disinhibiting effects create particular risk in social or unfamiliar settings, where impaired judgment may go unnoticed. The subjective sense of functioning normally while objectively impaired is a recognized class effect that increases risk-taking during intoxication.

Aftercare & integration. Temazepam is a sedative-hypnotic, and post-use care focuses on managing residual impairment and addressing the underlying sleep problem. Morning-after grogginess, slowed reactions, and subtle memory suppression can persist for several hours — plan accordingly for driving, work, and decisions.

If temazepam has been used nightly for more than a few weeks, stopping should be gradual and ideally supervised. Rebound insomnia is common and temporary but can feel severe enough to drive immediate reinstatement. Non-pharmacological sleep strategies — consistent sleep schedule, reduced evening stimulation, cognitive behavioral therapy for insomnia — are the foundation of long-term improvement.

Recovery & Support

Benzodiazepine dependence is a well-recognized medical condition with established treatment pathways. Gradual dose tapering — reducing in small steps over weeks to months — is the standard approach and far safer than stopping abruptly, which risks seizures and severe rebound symptoms.

Medical supervision during taper is strongly recommended. Some patients benefit from switching to a longer-acting benzodiazepine such as diazepam to smooth the reduction. Melatonin has been studied as a supportive aid during benzodiazepine withdrawal in older adults.[28]

Support resources include the SAMHSA National Helpline (1-800-662-4357), the Benzodiazepine Information Coalition, and peer support communities. Dependence on a prescribed medication is not a moral failing — it is a predictable physiological adaptation that responds to structured treatment.

Recovery resources, crisis lines, and support pathways → View all

Emergency Response

Recognizing an emergency:

  • Breathing becomes very slow, shallow, or stops
  • Lips or fingertips turn blue or gray
  • The person cannot be woken by loud voice or sternal rub
  • Seizures occur
  • Severe confusion or agitation beyond normal sedation

Immediate steps:

  • 1. Call emergency services immediately if breathing is compromised, the person is unresponsive, or seizures occur.
  • 2. Place the person in the recovery position (on their side) to protect the airway.
  • 3. Do not induce vomiting.
  • 4. Stay with the person and monitor breathing until help arrives.
  • 5. If opioids may also have been taken and naloxone is available, administer it — naloxone reverses opioid but not benzodiazepine effects.

What to tell the dispatcher: Name the substance (temazepam / benzodiazepine), estimated amount taken, time of ingestion, any other substances involved, and current symptoms. Good Samaritan laws in many jurisdictions protect people who call for help during a drug emergency.

Reversal agent: Flumazenil can reverse benzodiazepine effects but carries risks of seizure and dangerous heart rhythm changes. It is administered only in hospital settings — do not delay calling emergency services in anticipation of reversal.

Safety[edit]

Harm
Acute toxicity
Low
Chronic toxicity
Moderate
Withdrawal
Severe
Tolerance buildup
moderate
Tolerance reset
10.5 days
Dependence
Physical
High
Psychological
Moderate
Compulsive redosing
Moderate
Dose escalation
Moderate
Cross-tol.
benzodiazepines · barbiturates · zolpidem
Risk Shape
TOXPHYPSYWDRREDTOL

Toxicity

Acute toxicity

Temazepam overdose presents with excessive sedation, confusion, impaired coordination, diminished reflexes, slowed breathing, and in severe cases, coma.[2] Temazepam alone is rarely fatal; nearly all temazepam-related deaths involve co-ingestion with other depressants — particularly opioids and alcohol — which produce combined respiratory depression exceeding what either substance causes alone.[5]

StatPearls states that temazepam is "approximately 10 times more hazardous than diazepam" in overdose.[2] This claim could not be traced to a primary published source.safety citation needed No published lethal dose data exist for temazepam in humans or animals.safety citation needed

Injection toxicity

Temazepam must never be injected by any route. The compound is nearly insoluble in water and directly damages blood vessel walls.[3] Injected material solidifies at body temperature, causing mechanical blockage on top of chemical injury. In clinical case series, all patients who injected temazepam into arteries suffered severe tissue death; injection into the radial artery invariably required amputation.[4][10] Documented complications include abscesses, skin ulceration, nerve damage, blood clots, gangrene, and muscle breakdown.[2][3]

Respiratory effects

In patients with severe stable COPD, temazepam 10 mg did not significantly impair breathing or gas exchange.[21] However, benzodiazepines are contraindicated in obstructive sleep apnea because muscle relaxation can worsen airway collapse. Respiratory depression remains the primary mechanism of death in polydrug overdose.

Pregnancy

Temazepam carries FDA pregnancy Category X designation. Animal studies documented birth defects including skull malformations and rib abnormalities. Benzodiazepine exposure during pregnancy is associated with neonatal withdrawal characterized by low muscle tone, breathing difficulties, and low body temperature.[2]

Elderly

Falls are the primary safety concern in older adults taking temazepam. Hypnotic medications impair balance and standing steadiness.[22] Temazepam and triazolam carry similar hip fracture risk.[23] A meta-analysis of 24 trials found harmful cognitive effects 4.78 times more common with sedative-hypnotics than placebo in older adults (95% CI 1.47–15.47).[24]

Overdose management

Flumazenil can reverse benzodiazepine effects but is not recommended for routine overdose management. A meta-analysis found significantly more adverse events with flumazenil than placebo, including dangerous heart rhythm changes and seizures.[25] Standard overdose management is supportive care: maintaining the airway and monitoring vital signs.

Psychological risks

Temazepam produces dose-dependent anterograde amnesia — impaired ability to form new memories during the period of drug activity.[18] At therapeutic doses, this appears as difficulty recalling events after ingestion; at higher doses, complete memory gaps may occur.

Disinhibition is a recognized benzodiazepine class effect. Post-marketing reports include rare paradoxical reactions — agitation, aggression, and paranoia — more common in elderly patients and those with pre-existing psychiatric conditions.[2]

Delusions of sobriety — the belief that one is functioning normally while objectively impaired — may drive dose escalation and risky behavior during intoxication.

Rebound insomnia affects 26–58% of users following discontinuation of temazepam 20 mg,[26] often accompanied by mood disturbance.[6] Vivid dreams and nightmares are reported as adverse effects during use.[2]

Tolerance & dependence

Tolerance to temazepam's sleep-promoting effect develops with continued use. Controlled sleep laboratory studies demonstrated significant tolerance within 14–22 nights of nightly dosing.[6] Contrasting findings from a 3-month clinical trial (n = 175) showed temazepam 30 mg maintaining efficacy without tolerance,[20] suggesting tolerance development may depend on individual factors and measurement context.

Cross-tolerance exists with all benzodiazepines and other GABA-A modulators.[27]

Physical dependence develops with regular use and produces a withdrawal syndrome on cessation. Symptoms include rebound effect insomnia, anxiety, agitation, tremor, sensory disturbances, and autonomic instability; rarely, seizures and delirium occur.[7][27]

  • Onset: 1–3 days after last dose
  • Duration: Typically weeks; some patients experience protracted withdrawal lasting months
  • Management: Gradual dose reduction is preferred over abrupt cessation. Melatonin has been studied as an aid to benzodiazepine withdrawal in older patients[28]
1LETHAL
21DANGEROUS
26CAUTION
12UNGRADED
60 rules0 SOURCE-VERIFIED1 EDITOR-REVIEWED

Temazepam's interaction profile is dominated by pharmacodynamic effects — additive depression with other sedating substances — rather than metabolic drug-drug interactions. Because temazepam bypasses the CYP450 enzyme system,[2][1] the extensive metabolic interactions seen with alprazolam, triazolam, and midazolam do not apply.

Opioid co-administration produces additive respiratory depression and is a leading cause of drug-related death. The FDA has issued a boxed warning against concurrent benzodiazepine-opioid prescribing.[2][5]

Alcohol co-use produces combined depressant effects with potentially fatal respiratory failure.[5] Other benzodiazepines, barbiturates, sedating antihistamines, antipsychotics, and phenothiazines carry additive depressant risk.[2]

MAO inhibitors are listed as moderate interactants, though the precise interaction mechanism is not fully characterized.[2]

Contraindications

11 known
4ABSOLUTE
7RELATIVE

Absolute contraindications:

  • Pregnancy (FDA Category X): Documented birth defects in animal models and neonatal withdrawal in humans[2]
  • Known hypersensitivity to temazepam or other benzodiazepines[2]
  • Acute narrow-angle glaucomacitation needed

Relative contraindications:

  • Obstructive sleep apnea: Muscle relaxation may worsen airway collapse
  • Severe liver disease: Although temazepam's primary metabolism avoids CYP enzymes, severe liver impairment may affect all metabolic pathways
  • Myasthenia gravis: Muscle-relaxant effects may worsen neuromuscular weakness[2]
  • Acute alcohol intoxication: Additive depressant risk[2]
  • Severe depression with suicidal thoughts: Depressant effects and disinhibition may increase suicide risk[2]
  • History of substance use disorder: Elevated misuse and dependence risk[7]
  • Elderly patients: Increased sensitivity and fall risk warrant particular caution[1][24]

Harm Reduction[edit]

Forms & Identification

Reagent ResultsNot recorded+ add reagent results
AppearanceNot recorded+ add appearance
Red FlagsNot recorded+ add red flags

Pharmaceutical temazepam tablets are manufactured with consistent dosing and identifiable by imprint codes. The primary identification concern is not adulteration of genuine pharmacy stock but verifying that tablets obtained outside a pharmacy are genuinely temazepam rather than counterfeit products containing more potent benzodiazepines or other active compounds. Reagent testing does not reliably distinguish between different benzodiazepines; pill identification databases matching imprint codes provide the most practical verification for pharmaceutical tablets.

Guidelines

  • Take only the prescribed dose. Higher doses intensify amnesia and psychomotor impairment without proportionally improving sleep quality.
  • Take temazepam immediately before getting into bed. Walking around, socializing, or using the phone after dosing increases the likelihood of amnestic behavior and impaired decisions.
  • Allow a full 7–8 hours for sleep. Taking temazepam without sufficient time for sleep increases morning-after impairment.
  • Do not drive or operate machinery the morning after use until certain that alertness has fully returned.
  • Do not use nightly for more than 2–3 weeks without medical review. Tolerance to the sleep-promoting effect develops within this window, and physical dependence begins.
  • Never crush, dissolve, or inject tablets. Injection of temazepam in any form causes severe vascular injury.

Set & Setting

Temazepam is a sedative-hypnotic taken primarily at bedtime. The environment should support safe sleep: a secure location where the user will not need to drive, operate machinery, or make important decisions. Because temazepam produces anterograde amnesia, anything requiring memory formation — conversations, commitments, financial decisions — should be completed before dosing.

The amnestic and disinhibiting effects make temazepam particularly risky in social or unfamiliar settings where impaired judgment may go unnoticed. The subjective sense of normal functioning while objectively impaired (delusions of sobriety) is a recognized class effect that increases risk-taking during intoxication.

Aftercare & integration. Temazepam is a sedative-hypnotic, and post-use care focuses on managing residual impairment and addressing the underlying sleep problem. Morning-after grogginess, slowed reaction time, and subtle memory suppression can persist for several hours after waking — plan accordingly for driving, work, and decision-making.

If temazepam has been used nightly for more than a few weeks, discontinuation should be gradual and ideally supervised. Rebound insomnia is common and temporary but can feel severe enough to drive immediate reinstatement of use. Non-pharmacological sleep strategies — consistent sleep schedule, reduced evening stimulation, cognitive behavioral therapy for insomnia — are the foundation of long-term sleep improvement.

Recovery & Support

Benzodiazepine dependence is a well-recognized medical condition with established treatment pathways. Gradual dose tapering — reducing the dose in small steps over weeks to months — is the standard approach and is far safer than abrupt cessation, which risks seizures and severe rebound symptoms.

Medical supervision during taper is strongly recommended. Some patients benefit from switching to a longer-acting benzodiazepine (such as diazepam) to smooth the reduction curve. Melatonin has been studied as a supportive aid during benzodiazepine withdrawal in older adults.[28]

Support resources include the SAMHSA National Helpline (1-800-662-4357), the Benzodiazepine Information Coalition, and peer support communities. Dependence on a prescribed medication is not a moral failing — it is a predictable physiological adaptation that responds to structured treatment.

Recovery resources, crisis lines, and support pathways → View all

Emergency Response

Recognizing an emergency:

  • Breathing becomes very slow, shallow, or stops
  • Lips or fingertips turn blue or gray
  • The person cannot be woken by loud voice or sternal rub
  • Seizures occur
  • Severe confusion or agitation beyond normal sedation

Immediate steps:

  • 1. Call emergency services immediately if breathing is compromised, the person is unresponsive, or seizures occur.
  • 2. Place the person in the recovery position (on their side) to protect the airway.
  • 3. Do not induce vomiting.
  • 4. Stay with the person and monitor breathing until help arrives.
  • 5. If opioids may also have been taken and naloxone is available, administer it — naloxone reverses opioid but not benzodiazepine effects.

What to tell the dispatcher: Name the substance (temazepam / benzodiazepine), estimated amount taken, time of ingestion, any other substances involved, and current symptoms. Good Samaritan laws in many jurisdictions protect people who call for help during a drug emergency.

Reversal agent: Flumazenil can reverse benzodiazepine effects but carries risks of seizure and dangerous heart rhythm changes. It is administered only in hospital settings — do not delay calling emergency services in anticipation of reversal.

Frequently asked questions

What is Temazepam?

Temazepam is a 3-hydroxybenzodiazepine hypnotic and non-selective GABA-A positive allosteric modulator, first synthesized in 1964. It is metabolized primarily by glucuronide conjugation rather than CYP oxidation, producing an intermediate half-life of 3.5–18.4 hours.

How long does Temazepam last?

Total duration by route of administration — Oral: 7 – 8 hours. Ranges vary with dose and individual factors; see the duration table for onset, peak, and after-effect phases.

Where can I find dosage information for Temazepam?

Psychedex publishes a dosage table for Temazepam on this page covering these routes of administration: oral. Dose values are presented only in that table, always alongside their route of administration.

What are dangerous combinations with Temazepam?

The highest-severity documented interactions for Temazepam: Opioids (Lethal), Alpha-2 adrenergic receptor antagonist (Dangerous), Antipsychotics (Dangerous), Atypical antipsychotics (Dangerous), Benzodiazepines (Dangerous). See the interactions section for the full list with mechanisms and severity levels.

Is Temazepam addictive?

Psychedex records tolerance and dependence data rather than a yes/no rating. Recorded tolerance indicators for Temazepam: tolerance builds moderate; full reset takes 10.5 days; cross-tolerance develops with benzodiazepines, barbiturates, zolpidem, zopiclone, zaleplon, alcohol. See the article's dependence and safety sections for recorded dependence data.

experience reports

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First-person accounts of subjective effects, timing, and outcomes — submitted for harm reduction.

references

  1. [1] 
    ^abcdeGreenblatt DJ, Harmatz JS, Shader RI (1991) Clinical Pharmacokinetics of Anxiolytics and Hypnotics in the Elderly — Clinical Pharmacokinetics doi:10.2165/00003088-199121030-00002
  2. [2] 
    ^abcdefghijklmnopqrstStatPearls Publishing (2024) Temazepam - StatPearls Link
  3. [3] 
    ^abcdefgAustralian Prescriber (2004) Temazepam capsules: what was the problem? Link
  4. [4] 
    ^abcDodd TJ, Scott RN, Woodburn KR, Going JJ (1994) Limb ischaemia after intra-arterial injection of Temazepam gel: histology of nine cases — Journal of clinical pathology PMID:8063932
  5. [5] 
    ^abcdeKales A, Bixler EO, Soldatos CR, et al. (1986) Quazepam and temazepam: effects of short- and intermediate-term use and withdrawal — Clinical pharmacology and therapeutics PMID:2868823
  6. [6] 
    ^abcLader M (1994) Anxiolytic drugs: dependence, addiction and abuse — European neuropsychopharmacology PMID:7919947

references

  1. [1] 
    ^abcdefGreenblatt DJ, Harmatz JS, Shader RI (1991) Clinical Pharmacokinetics of Anxiolytics and Hypnotics in the Elderly — Clinical Pharmacokinetics doi:10.2165/00003088-199121030-00002
  2. [2] 
    ^abcdefghijklmnopqrstuStatPearls Publishing (2024) Temazepam - StatPearls Link
  3. [3] 
    ^abcdefgAustralian Prescriber (2004) Temazepam capsules: what was the problem? Link
  4. [4] 
    ^abcDodd TJ, Scott RN, Woodburn KR, Going JJ (1994) Limb ischaemia after intra-arterial injection of Temazepam gel: histology of nine cases — Journal of clinical pathology PMID:8063932
  5. [5] 
    ^abcdGudin JA, Mogali S, Jones JD, Comer SD (2013) Risks, management, and monitoring of combination opioid, benzodiazepines, and/or alcohol use — Postgraduate medicine doi:10.3810/pgm.2013.07.2684
  6. [6] 
    ^abcdeKales A, Bixler EO, Soldatos CR, et al. (1986) Quazepam and temazepam: effects of short- and intermediate-term use and withdrawal — Clinical pharmacology and therapeutics PMID:2868823
Last updated Jun 4, 2026