Flurazepam is a member of the benzodiazepines and a long-acting depressor of the central nervous system (CNS) with sedative and hypnotic effects. Flurazepam binds to a specific site on the benzodiazepine-gamma-aminobutyric acid (GABA)-A-chloride ionophore receptor complex located on the neuronal membrane. Binding causes an allosteric modification of the receptor thereby enhancing the affinity of GABA to the receptor leading to an increase in the frequency of chloride-channel opening events, which leads to an increase in chloride ion conductance, neuronal hyperpolarization, inhibition of the action potential, and a decrease in neuronal excitability. By modulating binding of the GABA inhibitory neurotransmitter to GABA-A receptors in the ascending reticular activating system, flurazepam blocks arousal of the cortical and limbic system, thereby exerting its sedative and hypnotic effect.
Flurazepam is a drug which is a benzodiazepine derivative. It possesses anxiolytic, anticonvulsant, hypnotic, sedative and skeletal muscle relaxant properties. It produces a metabolite with a long half-life, which may stay in the bloodstream for days.
Mechanism of Action of Flurazepam
Flurazepam binds to an allosteric site on GABA-A receptors. Binding potentiates the action of GABA on GABA-A receptors by opening the chloride channel within the receptor, causing chloride influx and hyperpolarization.
Indications of Flurazepam
- Sleeplessness
- Insomnia
- For short-term and intermittent use in patients with recurring insomnia and poor sleeping habits
- Anti-Anxiety Agents, Benzodiazepine; GABA Modulators; Sedatives, Nonbarbiturate
Contra-Indications of Flurazepam
- Myasthenia gravis
- Acute intoxication with alcohol, narcotics, or other psychoactive substances
- Ataxia
- Severe hypoventilation
- Acute narrow-angle glaucoma
- Severe liver deficiencies (hepatitis and liver cirrhosis decrease elimination by a factor of 2)
- Mental Disorder with Loss of Normal Personality & Reality
- Having Thoughts of Suicide
- Drug abuse
- Severe Chronic Obstructed Lung Disease
- Temporarily Stops Breathing While Sleeping
- Shock
- Pregnancy
- Hypersensitivity or allergy to any drug in the benzodiazepine class
Dosage of Flurazepam
Strengths: 15 mg; 30 mg
Insomnia
- 15 mg orally once a day at bedtime for women and 15 or 30 mg orally once a day at bedtime for men
Side Effects of Flurazepam
The most common
- Dry mouth
- muscle trembling, jerking, or stiffness
- agitation
- anxiety
- changes in vision, including blurred vision
- dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
- Chest pain or tightness
- trembling or shaking of the hands or feet
- stomach pain or cramping
- diarrhea
- headache
- stomach pain;
- back pain, joint or muscle pain.
- problems with your vision (including color vision);
- sudden chest pain or trouble breathing;
- pain or swelling in one or both legs;
- migraine headache;
- pale skin, feeling light-headed or short of breath, rapid heart rate, trouble concentrating; or
More common
- Abdominal or stomach pain, discomfort, or tenderness
- chills or fever
- difficulty with moving
- headache, severe and throbbing
- joint or back pain
- muscle aching or cramping
- muscle pains or stiffness
- chest pressure or squeezing pain in chest
- discomfort in arms, shoulders, neck or upper back
- excessive sweating
- feeling of heaviness, pain, warmth and/or swelling in a leg or in the pelvis
- sudden tingling or coldness in an arm or leg
- sudden slow or difficult speech
- sudden drowsiness or need to sleep
- fast breathing
- sharp pain when taking a deep breath
- fast or slow heartbeat
- coughing up blood
- rust colored urine
- decreased amount of urine
Rare
- Anxiety
- change in vision
- chest pain or tightness
- confusion
- cough
- Agitation
- arm, back, or jaw pain
- blurred vision
- chest pain or discomfort
- convulsions
- extra heartbeats
- fainting
- hallucinations
- headache
- irritability
- lightheadedness
- mood or mental changes
- muscle pain or cramps
- muscle spasm or jerking of all extremities
- nervousness
Drug Interactions of Flurazepam
Flurazepam may interact with following drug, supplements, & may change the efficacy of the drug
- ACE inhibitors, Adrenergic neurone blockers, Angiotensin II receptor antagonists, Beta blockers, Calcium channel blockers, Clonidine, Diazoxide, Diuretics, Hydralazine, Methyldopa, Minoxidil, Nitrates, Sodium Nitroprusside – enhanced hypotensive effect
- Alcohol, barbiturates, opiates, antihistamines, antipsychotics – increased sedative effect in combination with benzodiazepines.
- Cimetidine – metabolism of benzodiazepines inhibited by cimetidine (increased plasma concentration)
- Disulfiram – metabolism of benzodiazepines inhibited by disulfiram (increased sedative effects)
- Fluvoxamine – plasma concentration of some benzodiazepines increased by fluvoxamine
- Levodopa – benzodiazepines possibly antagonize effects of levodopa
- Moxonidine – sedative effects possibly increased when benzodiazepines given with moxonidine
- Olanzapine – increased risk of hypotension, bradycardia and respiratory depression when parenteral benzodiazepines given with intramuscular olanzapine
- Phenytoin – benzodiazepines possibly increase or decrease the plasma concentration of phenytoin
- Rifampicin – metabolism of benzodiazepines possibly accelerated by rifampicin (reduced plasma concentration)
- Sodium oxybate – benzodiazepines enhance effects of sodium oxybate (avoid concomitant use)
Pregnancy Catagory of Flurazepam
FDA Pregnancy Category N – Not classified.
Pregnancy
Benzodiazepines may cause fetal damage when administered during pregnancy. Therefore, flurazepam should not be used during pregnancy. Women should be warned of the potential risks to the fetus if they become pregnant while taking flurazepam.
Lactation
It is not known if flurazepam crosses into human milk. Because many medications can cross into human milk and because of the possibility for serious adverse reactions in nursing infants with use of this medication, a choice should be made whether to stop nursing or stop the use of this medication. Your doctor and you will decide if the benefits outweigh the risk of using flurazepam.
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