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Flurazepam (Monograph)

Brand name: Formerly available as Dalmane
Drug class: Benzodiazepines
VA class: CN302
CAS number: 1172-18-5

Medically reviewed by on Sep 26, 2022. Written by ASHP.


    Concomitant Use with Opiates
  • Concomitant use of benzodiazepines and opiates may result in profound sedation, respiratory depression, coma, and death.

  • Reserve concomitant use for patients in whom alternative treatment options are inadequate; use lowest effective dosages and shortest possible duration of concomitant therapy and monitor closely for respiratory depression and sedation. (See Specific Drugs under Interactions.)

    Potential for Abuse, Addiction, and Other Serious Risks
  • A boxed warning has been included in the prescribing information for all benzodiazepines describing risks of abuse, misuse, addiction, physical dependence, and withdrawal reactions.

  • Abuse and misuse can result in overdose or death, especially when benzodiazepines are combined with other medicines, such as opioid pain relievers, alcohol, or illicit drugs.

  • Assess a patient’s risk of abuse, misuse, and addiction. Standardized screening tools are available ([Web]).

  • To reduce risk of acute withdrawal reactions, use a gradual dose taper when reducing dosage or discontinuing benzodiazepines. Take precautions when benzodiazepines are used in combination with opioid medications.


Benzodiazepine; sedative and hypnotic.

Uses for Flurazepam


Short-term management of insomnia. Has been used effectively for periods up to 4 weeks in duration.

Has been used effectively in individuals with difficulty in falling asleep, nocturnal awakenings, and/or early morning awakening.

May exhibit carryover effect (i.e., more effective on second, third, and fourth nights of use than on first night) because of accumulation of active metabolite. Effect may persist on first and sometimes second night after discontinuance.

Because of long half-life, may be more likely to result in residual sedative effects and in impaired psychomotor and mental performance during continued therapy, although partial tolerance to these effects can occur. Differences among hypnotics in residual and cumulative CNS depressant effects may be particularly important in geriatric patients, those with potentially impaired elimination of the drugs, and those whose job or life-style requires unimpaired intellectual or psychomotor function.

Flurazepam Dosage and Administration



Oral Administration

Administer at bedtime.


Available as flurazepam hydrochloride; dosage expressed in terms of the salt.



Usual dosage is 30 mg at bedtime. In some patients, 15 mg may be adequate.

Special Populations

Hepatic Impairment

Reduce dosage. Use smallest effective dosage.

Renal Impairment

No specific dosage recommendations.

Geriatric or Debilitated Patients

Initial dose of 15 mg at bedtime. Use smallest effective dosage.

Cautions for Flurazepam




Concomitant Use with Opiates

Concomitant use of benzodiazepines, including flurazepam, and opiates may result in profound sedation, respiratory depression, coma, and death. Substantial proportion of fatal opiate overdoses involve concurrent benzodiazepine use.

Reserve concomitant use of flurazepam and opiates for patients in whom alternative treatment options are inadequate. (See Specific Drugs under Interactions.)

Fetal/Neonatal Morbidity and Mortality

May cause fetal harm; avoid use of benzodiazepines as hypnotics during pregnancy. If used during pregnancy or if patient becomes pregnant, apprise of potential fetal hazard.

Adequate Patient Evaluation

Insomnia may be a manifestation of an underlying physical and/or psychiatric disorder; carefully evaluate patient before providing symptomatic treatment.

Failure of insomnia to remit after 7–10 days of treatment, worsening of insomnia, or emergence of new abnormal thinking or behavior may indicate the presence of an underlying psychiatric and/or medical condition.

Complex Sleep-related Behaviors

Potential risk of complex sleep-related behaviors such as sleep-driving (i.e., driving while not fully awake after ingesting a sedative-hypnotic drug with no memory of the event), making phone calls, or preparing and eating food, while asleep.

Adverse Psychiatric Events

Abnormal thinking and behavioral changes (e.g., aggressiveness, uncharacteristic extroversion, bizarre behavior, agitation, hallucinations, depersonalization, amnesia) may occur in patients receiving benzodiazepines.

Immediately evaluate any new behavioral sign or symptom.

CNS Depression

Performance of activities requiring mental alertness and physical coordination may be impaired.

Concurrent use of other CNS depressants may cause additive or potentiated CNS depression. (See Concomitant Use with Opiates under Cautions and also see Specific Drugs under Interactions.)

Dependence and Abuse Potential

Psychologic and physical dependence may occur following prolonged use.

Patients with a history of drug or alcohol dependence or abuse are at risk of habituation or dependence; use only with careful surveillance in such patients.

Tolerance and Withdrawal Effects

Tolerance may occur following prolonged benzodiazepine use.

Abrupt discontinuance may result in symptoms of withdrawal (similar to barbiturates or alcohol).

Sensitivity Reactions

Potential risk of anaphylaxis and angioedema; may occur even with the first dose of drug.

General Precautions


Use with caution in depressed patients; potential for suicidal tendencies. Prescribe and dispense drug in the smallest feasible quantity.

Respiratory Effects

Use with caution in patients with compromised pulmonary function.

Specific Populations


Category X. (See Fetal/Neonatal Morbidity and Mortality under Cautions.)

If used during the last weeks of pregnancy, potential for neonatal CNS depression.


Benzodiazepines generally are distributed into milk; not known whether flurazepam is distributed into milk, but distribution into milk should be expected.

Pediatric Use

Safety and efficacy not established in children <15 years of age.

Geriatric Use

Potential increased sensitivity (increased risk of oversedation, dizziness, confusion, and/or ataxia); use low initial dose and monitor closely.

Half-life of desalkylflurazepam is prolonged following multiple doses in geriatric men and women and after single-dose administration in geriatric men.

Hepatic Impairment

Use with caution. Use reduced dosage.

Renal Impairment

Use with caution.

Common Adverse Effects

Dizziness, drowsiness, lightheadedness, staggering, ataxia, falling (particularly in geriatric or debilitated patients).

Drug Interactions

Specific Drugs





Possible decreased plasma clearance of flurazepam

Use with caution; consider flurazepam dosage reduction


Severe hypotension, respiratory or cardiac arrest, and loss of consciousness reported when benzodiazepines (including flurazepam) were given with or within 24 hours before clozapine

Use with caution

Some clinicians recommend discontinuance of benzodiazepine therapy ≥1 week prior to initiation of clozapine

CNS depressants (alcohol, anticonvulsants, sedatives)

Additive CNS depressant effects

Do not use alcohol concomitantly with hypnotics; caution if other CNS depressants are used concomitantly with flurazepam


Possible inhibition of flurazepam metabolism

Observe closely for enhanced benzodiazepine response

Consider possible need for flurazepam dosage reduction

Opiate agonists and partial agonists

Risk of profound sedation, respiratory depression, coma, or death

Whenever possible, avoid concomitant use

Opiate analgesics: Use concomitantly only if alternative treatment options are inadequate; use lowest effective dosages and shortest possible duration of concomitant therapy; monitor closely for respiratory depression and sedation

In patients receiving flurazepam, initiate opiate analgesic, if required, at reduced dosage and titrate based on clinical response

In patients receiving an opiate analgesic, initiate flurazepam, if required, at lower dosage than indicated in the absence of opiate therapy and titrate based on clinical response

Opiate antitussives: Avoid concomitant use

Consider offering naloxone to patients receiving benzodiazepines and opiates concomitantly

Flurazepam Pharmacokinetics



Rapidly absorbed from the GI tract, with peak plasma concentration achieved within 30–60 minutes.


Onset of hypnotic effect occurs within 15–45 minutes.


Hypnotic effect persists for 7–8 hours.



Benzodiazepines are widely distributed into body tissues and cross the blood-brain barrier.

Benzodiazepines and their metabolites generally cross the placenta and are distributed into milk. Not known whether flurazepam is distributed into milk, but distribution into milk should be expected.

Plasma Protein Binding

Benzodiazepines and their metabolites are highly bound to plasma proteins.



Undergoes first-pass metabolism in the liver; major metabolites are N-1-desalkylflurazepam and N-1-hydroxyethylflurazepam. Hydroxylated metabolite undergoes subsequent conjugation.

Elimination Route

Eliminated mainly in the urine; 25–55% of dose recovered as conjugates of N-1-hydroxyethylflurazepam, and <1% recovered as N-1-desalkylflurazepam.


Flurazepam: 2.3 hours.

N-1-Desalkylflurazepam: 47–100 hours.

N-1-Hydroxyethylflurazepam: 2–4 hours.

Special Populations

Geriatric men: Desalkylflurazepam half-life of 160 or 126 hours (after single or multiple doses, respectively) versus 74 or 111 hours in younger males.

Geriatric women: Desalkylflurazepam half-life of 120 or 158 hours (after single or multiple doses, respectively) versus 90 or 113 hours in younger females.

In patients with liver disease, elimination half-life may be prolonged.

Benzodiazepines are not appreciably removed by hemodialysis.





25°C (may be exposed to 15–30°C).


Advice to Patients


Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Subject to control under the Federal Controlled Substances Act of 1970 as a schedule IV (C-IV) drug.

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Flurazepam Hydrochloride


Dosage Forms


Brand Names




15 mg*

Flurazepam Hydrochloride Capsules (C-IV)

30 mg*

Flurazepam Hydrochloride Capsules (C-IV)

AHFS DI Essentials™. © Copyright 2024, Selected Revisions September 26, 2022. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.

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