- 1. Name of the medicinal product
- 2. Qualitative and quantitative composition
- 3. Pharmaceutical form
- 4. Clinical particulars
- 4.1 Therapeutic indications
- 4.2 Posology and method of administration
- 4.3 Contraindications
- 4.4 Special warnings and precautions for use
- 4.5 Interaction with other medicinal products and other forms of interaction
- 4.6 Pregnancy and lactation
- 4.7 Effects on ability to drive and use machines
- 4.8 Undesirable effects
- 4.9 Overdose
- 5. Pharmacological properties
- 5.1 Pharmacodynamic properties
- 5.2 Pharmacokinetic properties
- 5.3 Preclinical safety data
- 6. Pharmaceutical particulars
- 6.1 List of excipients
- 6.2 Incompatibilities
- 6.3 Shelf life
- 6.4 Special precautions for storage
- 6.5 Nature and contents of container
- 6.6 Special precautions for disposal and other handling
- Administrative data
- 7. Marketing authorisation holder
- 8. Marketing authorisation number(s)
- 9. Date of first authorisation/renewal of the authorisation
- 10. Date of revision of the text
Adults:1) The short term relief (14 days) only of anxiety which is severe, disabling or subjecting the individual to unacceptable distress, occurring alone or in association with insomnia or short-term psychosomatic, organic or psychotic illness.The use of benzodiazepines to treat short-term anxiety is considered to be inappropriate.2) Cerebral palsy.3) Muscle spasm; as an adjunct to the control of muscle spasm in tetanus.4) As an adjunct to the management of certain types of epilepsy (eg myoclonus).5) Symptomatic treatment of acute alcohol withdrawal.6) As oral premedication for the nervous dental patient.
Children:1) Control of tension and irritability in cerebral spasticity in selected cases.2) Oral premedication.
PosologyAs an anxiolytic, the lowest effective dose should be employed; dosage regimes should not exceed beyond 14 days. Patients who have received benzodiazepines for a long time may require an extended withdrawal period. Long-term chronic use is not recommended.
Adults:Anxiety states, obsessive-compulsive neuroses, and other psychiatric disorders: 2-30mg daily in divided doses.Insomnia associated with anxiety: 5-30mg before retiring.Cerebral palsy: 2-60mg daily in divided doses.Upper motor neuronic spasticity: 5-60mg daily in divided doses.Muscle spasm of varied aetiology, fibrositis, cervical spondylosis: 2-15mg daily in divided doses.Adjunct to the management of some types of epilepsy: Premedication: 2-60mg daily in divided doses. Adults: 5-20mg and children: 2-10mg.Alcohol withdrawal: 5-20mg, repeated if necessary in 2 to 4 hours.Oral premedication in dental patients: 5mg the night before, 5mg on waking and 5mg two hours before the appointment. Children: Conditions associated with muscle spasm: Control of tension and irritability in spasticity in selected cases; 2-40mg daily in divided doses. As an adjunct to the control of muscle spasm in tetanus; as for adults.Spastic children with minimal brain damage: 2-40mg daily in divided doses. Elderly and debilitated patients: Doses should not exceed half the above recommended adult doses. Method of Administration For oral administration.
Psychiatric and 'paradoxical' reactionsParadoxical reactions (such as restlessness, agitation, irritability, aggressiveness, delusion, rages, nightmares, hallucinations, psychoses, inappropriate behaviour and other adverse behavioural effects) have been reported from the use of benzodiazepines.Such reactions are possibly seen more often in the treatment of children and elderly patients and should result in the discontinuation of treatment.Potentially suicidal individuals should not have access to large amounts of diazepam due to the risk of overdosing.
AlcoholDiazepam should not be used together with alcohol (CNS inhibition enhanced sedative effects: impaired ability to drive/ operate machinery).
Sodium oxybateAvoid concomitant use (enhanced effects of sodium oxybate).
HIV-protease inhibitorsAvoid concomitant use (increased risk of prolonged sedation) see below for zidovudine.
Take into account
Pharmacodynamic interactionsIf diazepam is used with other centrally acting agents, careful consideration has to be given to the pharmacology of the agents employed, particularly with compounds that may potentiate or be potentiated by the action of diazepam, such as neuroleptics, anxiolytics/sedatives, hypnotics, antidepressants, anticonvulsants, sedating antihistamines, antipsychotics, anaesthetics for general anaesthesia and narcotic analgesics. Such concomitant use may increase sedative effects and cause depression of respiratory and cardiovascular functions. Concomitant use of narcotic analgesics may promote psychic dependency due to enhancement of euphorigenic effects.
Anti-epileptic drugsPharmacokinetic studies on potential interactions between diazepam and antiepileptic drugs have produced conflicting results. Both depression and elevation of drug levels, as well as no change, have been reported. Phenobarbital taken concomitantly may result in an additive CNS effect. Increased risk of sedation and respiratory depression. Phenobarbital is a known inducer of CYP3A4 and increases hepatic metabolism of diazepam. Reduced effect of diazepam.Special care should be taken in adjusting the dose in the initial stages of treatment. Side effects may be more evident with hydantoins or barbiturates. Diazepam has been reported to be displaced from protein-binding sites by sodium valproate (increased serum levels: increased risk of drowsiness).
Narcotic analgesicsEnhancement of the euphoria may lead to increased psychological dependence.
Other drugs enhancing the sedative effect of diazepamCisapride, lofexidine, nabilone, disulfiram and the muscle-relaxants baclofen, tizanidine, suxethonium and tubocurarin.
Compounds that affect hepatic enzymes (particularly cytochrome P450): Inhibitors (eg cimetidine: isoniazid: erythromycin: omeprazole: esomeprazole) reduce clearance and may potentiate the action of benzodiazepines. Itraconazloe, ketoconazole, and to a lesser extent fluconazole and voriconazole are potent inhibitors of the cytochrome P450 isoenzyme CYP3A4 and may increase plasma levels of benzodiapines. The effects of benzodiapines may be increased and prolonged by concomitant use. A dose reduction of the benzodiazepine may be required.
Rifamycins (rifampicin)Rifampicin is a potent inducer of CYP3A4 and substantially increases the hepatic metabolism and clearance of diazepam. In a study with healthy subjects administered 600 mg or 1.2 g rifampicin daily for 7 days, the clearance of diazepam was increased by about fourfold. Co-administration with rifampicin gives rise to substantially decreased concentrations of diazepam. Reduced effect of diazepam. The concomitant use of rifampicin and diazepam should be avoided.Antihypertensives, vasodilators& diuretics: Enhanced hypotensive effect with ACEinhibitors, alpha-blockers, angiotensinII receptor antagonists, calcium channel blockers adrenergic neurone blockers, beta-blockers, moxonidine, nitrates, hydralazine, minoxidil, sodium nitroprusside and diuretics. Enhanced sedative effect with alpha-blockers or moxonidine.
DopaminergicsPossible antagonism of the effect of levodopa.
AntacidsConcurrent use may delay absorption of diazepam.
Antiviral agents (atazanavir, ritonavir, delavirdine, efavirenz, indinavir, nelfinavir, saquinavir)Antiviral agents may inhibit the CYP3A4 metabolic pathway for diazepam. Increased risk of sedation and respiratory depression. Therefore, concomitant use should be avoided.
ZidivudineIncreased zidovudine clearance by diazepam.
Oral contraceptivesInhibition of oxidative metabolism of diazepam. Increased effects of diazepam. Co-administration of diazepam and combined oral contraceptives has been known to cause breakthrough bleeding. The mechanism of this reaction is unknown. Breakthrough bleeding, but no contraceptive failures have been reported.TheophyllineA proposed mechanism is competitive binding of theophylline to adenosine receptors in the brain. Counteraction of the pharmacodynamic effects of diazepam, e.g. reduction of sedation and psychomotor effects.
CaffeineConcurrent use may result in reduced sedative and anxiolytic effects of diazepam.
Grapefruit juiceInhibition of CYP3A4 may increase the plasma concentration of diazepam (possible increased sedation and amnesia). Cmax is increased by 1.5 times and AUC by 3.2 times. Possible increased effect of diazepam. This interaction may have little significance in healthy individuals, but it is not clear is if other factors such as old age or liver cirrhosis increase the risk of adverse effects with concurrent use.
ClozapineMechanism: Pharmacodynamic synergism.Effect: Severe hypotension, respiratory depression, unconsciousness and potentially fatal respiratory and/or cardiac arrest. Therefore, concomitant use is not recommended and should be avoided.
Pharmacokinetic interactionsDiazepam is mainly metabolised to the pharmacologically active metabolites N-desmethyldiazepam, temazepam and oxazepam. The oxidative metabolism of diazepam is mediated by CYP3A4 and CYP2C19 isoenzymes. Oxazepam and temazepam are further conjugated to glucuronic acid. Inhibitors of CYP3A4 and/or CYP2C19 can give rise to increased concentrations of diazepam while enzyme inducing drugs such as rifampicin, hypericum perforatum and certain antiepileptics can result in substantially decreased plasma concentrations of diazepam.
CarbamazepineCarbamazepine is a known inducer of CYP3A4 and increases hepatic metabolism of diazepam. This can result in up to three-fold greater plasma clearance and a shorter half-life of diazepam. Reduced effect of diazepam.
PhenytoinPhenytoin is a known inducer of CYP3A4 and increases hepatic metabolism of diazepam. Reduced effect of diazepam. The metabolism of phenytoin may be increased or decreased or remain unaltered by diazepam in an unpredictable way. Increased or decreased serum concentration of phenytoin. Phenytoin concentrations should be monitered more closely when diazepam is added or discontinued.
Azoles (fluconazole, itraconazole, ketoconazole, voriconazole)Increased plasma concentration of benzodiazepines, due to inhibition of the CYP3A4 and/or CYP2C19 metabolic pathway. Fluconazole: Co-administration with 400 mg fluconazole on the first day and 200 mg on the second day increased the AUC of a single 5 mg oral dose of diazepam 2.5-fold and prolonged the half-life from 31 hours to 73 hours.Voriconazole: A study with healthy subjects found that 400 mg voriconazole twice daily on the first day and 200 mg twice daily on the second day increased the AUC of a single 5 mg oral dose of diazepam 2.2-fold and prolonged the half-life from 31 hours to 61 hours.Increased risk of undesired effects and toxicity of benzodiazepine. Concomitant use should be avoided or the dose of diazepam reduced.
FluvoxamineFluvoxamine inhibits both CYP3A4 and CYP2C19 which leads to inhibition of the oxidative metabolism of diazepam. Co-administration with fluvoxamine results in an increased half-life and an approximately 190% increased plasma concentrations (AUC) of diazepam. Drowsiness, reduced psychomotor performance and memory. Preferably, benzodiazepines that are metabolised via a non-oxidative pathway should be used instead.
CorticosteroidsChronic use of corticosteroids may cause increased metabolism of diazepam due to induction of cytochrome P450 isoenzyme CYP3A4, or of enzymes responsible for glucuronidation. Reduced effects of diazepam.
CimetidineCimetidine inhibits the hepatic metabolism of diazepam, reducing its clearance and prolonging its half-life. In one stude where 300 mg cimetidine was administered four times daily for 2 weeks, the combined plasma level of diazepam and its active metabolite, desmethyldiazepam,was found to be increased by 57%, but reaction times and other motor and intellectual tests remained unaffected. Increased action of diazepam and increased risk of drowsiness. Reduction of the diazepam dose may be necessary.
OmeprazoleOmeprazole inhibits the CYP2C19 metabolic pathway for diazepam. Omeprazole prolongs the elimination half-life of diazepam and increases the plasma concentrations (AUC) of diazepam approximately between 30% - 120%. The effect is seen in CYP2C19 extensive metabolisers but not in slow metabolisers, with a low clearance of diazepam. Increased action of diazepam. Reduction of the diazepam dose may be necessary.
EsomeprazoleEsomeprazole inhibits the CYP2C19 metabolic pathway for diazepam. Co-administration with ezomeprazole results in an extended half-life and an increase in plasma concentrations (AUC) of diazepam by approximately 80%. Increased effect of diazepam. Reduction of the diazepam dose may be necessary.
IsoniazidIsoniazid inhibits the CYP2C19 and CYP3A4 metabolic pathway for diazepam. Co-administration with 90 mg isoniazid twice daily for 3 days resulted in a a prolonged elimination half-life of diazepam and in a 35% increased plasma concentration (AUC) of diazepam. Increased effect of diazepam.
ItraconazoleIncreased plasma concentration of diazepam due to inhibition of the CYP3A4 metabolic pathway. In a study with healthy subject given 200 mg itraconazole daily for 4 days increased the AUC of a single 5 mg oral dose of diazepam by about 15%, but there was no clinically significant interaction as determined by psychomotor performance tests. Possible increased effect of diazepam.
FluoxetineFluoxetine inhibits the metabolism of diazepam via CYP2C19 and other pathways, resulting in elevated plasma concentrations and decreased clearance of diazepam. Increased effect of diazepam. Concomitant use should be monitered closely.
DisulfiramReduced metabolism of diazepam leading to prolonged half-life and increased plasma concentration of diazepam. The elimination of the N-desmethyl metabolites of diazepam is slowed down which can give rise to marked sedative effects. Increased risk of CNS inhibition such as sedation.
CisaprideAccelerated absorption of diazepam. Temporary increase of the sedative effects of orally administered diazepam.
LevodopaConcomitant use with diazepam resulted in reduced effects of levodopa in a small number of case reports.
KetamineDue to similar oxidative processes, diazepam competitively inhibits ketamin metabolism. Pre-medication with diazepam leads to prolonged half-life of ketamine with enhanced effect as a result. Increased sedation.
PregnancyIf, for compelling medical reasons, the product is administered during the late phase of pregnancy, or during labour at high doses, effects on the neonate, such as hypothermia, hypotonia (Floppy Infant Syndrome), irregularities in the heart rate, poor suckling and moderate respiratory depression, can be expected, due to the pharmacological action of the compound.Moreover, infants born to mothers who took benzodiazepines chronically during the latter stages of pregnancy may have developed physical dependence and may be at some risk for developing withdrawal symptoms in the postnatal period.Studies in animals have shown reproductive toxicity (see section 5.3).
LactationBenzodiazepines are found in the breast milk -Reports have demonstrated milk: plasma concentration ratios to vary between 0.2 and 2.7. There is therefore a risk of accumulation in the breastfeeding child. Benzodiazepines should not be given to breast feeding mothers.
FertilityStudies in animals have shown a decrease in pregnancy rate and reduced number of surviving offspring in rats at high doses. There are no human data.
AmnesiaAnterograde amnesia may occur using therapeutic dosages, the risk increasing at higher dosages. Amnestic effects may be associated with inappropriate behaviour (see section 4.4).
DependenceChronic use (even at therapeutic doses) may lead to the development of physical and psychic dependence: discontinuation of the therapy may result in withdrawal or rebound phenomena (see section 4.4). Abuse of benzodiazepines has been reported.The frequencies of adverse events are ranked according to the following: Very common (≥1/10)Common (≥1/100 to <1/10)Uncommon (≥1/1,000 to <1/100)Rare (≥1/10,000 to <1/1,000)Very rare (<1/10,000)Not known (cannot be estimated from the available data).
|System Organ Class||Frequency||Undesirable effects|
|Blood and lymphatic system disorders||Rare||Blood dyscrasias|
|Immune system disorders||Very rare||Anaphylaxis.|
|Rare||Psychiatric and paradoxical reactions such as excitation, restlessness, agitation, irritability, aggressiveness, delusion, rages, hallucinations, psychoses, memory loss, nightmares, inappropriate behaviour and other adverse behavioural effects.a Emotional poverty, decreased alertness and depression.b|
|Nervous system disorders||Very common||Drowsiness.|
|Common||Ataxia, impaired motor ability, tremor.|
|Uncommon||Anterograde amnesia.c Concentration difficulties, balance disorders, dizziness, headache, slurred speech.|
|Rare||Unconsciousness, insomnia, dysarthria.|
|Eye disorders||Not known||Reversible disorders of vision: blurred vision, diplopia, nystagmus.|
|Cardiac disorders||Rare||Bradycardia, heart failure including cardiac arrest.|
|Vascular disorders||Rare||Hypotension, syncope.|
|Respiratory, thoracic and mediastinal disorders||Uncommon||Respiratory depression.|
|Rare||Respiratory arrest, increased bronchial secretion.|
|Gastrointestinal disorders||Uncommon||Gastrointestinal disorders (nausea, vomiting, constipation, diarrhoea), increased salivary secretion.|
|Rare||Dry mouth, increased appetite.|
|Hepatobiliary disorders||Rare||Jaundice, changes of hepatic parameters (elevation of ALT, AST, alkaline phosphatase).|
|Skin and subcutaneous tissue disorders||Uncommon||Allergic skin reactions (itching, erythema, rash).|
|Musculoskeletal and connective tissue disorders||Uncommon||Myasthenia.|
|Renal and urinary disorders||Rare||Urinary retention, incontinence.|
|Reproductive system and breast disorders||Rare||Gynaecomastia, impotence, increased or reduced libido.|
|General disorders and administration site conditions||Common||Fatigue, withdrawal symptoms (anxiety, panic, palpitations, sweating, tremor, gastrointestinal disorders, irritability, aggression, disrupted sensory perception, muscle spasms, general malaise, loss of appetite, paranoid psychosis, delirium and epileptic attacks).d|
|Investigations||Very rare||Elevation of transaminases.|
Reporting of suspected adverse reactionsReporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme; website: www.mhra.gov.uk/yellowcard
FeaturesThe symptoms of diazepam overdose are mainly an intensification of the therapeutic effects (ataxia, drowsiness, dysarthria, sedation, muscle weakness, profound sleep, hypotension, bradycardia, nystagmus) or paradoxical excitation. In most cases only observation of vital functions is required.Extreme overdosage may lead to coma, areflexia, cardiorespiratory depression and apnoea, requiring appropriate countermeasures (ventilation, cardiovascular support). Benzodiazepine respiratory depressant effects are more serious in patients with severe chronic obstructive airways disease. Severe effects in overdose also include rhabdomyolysis and hypothermia.
ManagementMaintain a clear airway and adequate ventilation.Consider activated charcoal (50g for an adult, 1g/kg for a child) in adults who have taken more than 100mg or children who have taken more than 1mg/kg within one hour, provided they are not too drowsy. Monitoring level of consciousness, respiratory rate, pulse oximetry and blood pressure in symptomatic patients. Consider arterial blood gas analysis in patients who have a reduced level of consciousness (GCS < 8; AVPU scale P or U) or have reduced oxygen saturations on pulse oximetry. Correct hypotension by raising the foot of the bed and by giving an appropriate fluid challenge. Where hypotension is thought mainly due to decreased systemic vascular resistance, drugs with alpha-adrenergic activity such as noradrenaline or high dose dopamine (10-30 micrograms/kg/min) may be beneficial. The dose of inotrope should be titrated against blood pressure.If severe hypotension persists despite the above measures, then central venous pressure monitoring should be considered.Supportive measures are indicated depending on the patient's clinical state.Benzodiazepines are not significantly removed from the body by dialysis.Flumazenil, a benzodiazepine antagonist, is not advised as a routine diagnostic test in patients with reduced conscious level. It may sometimes be used as an alternative to ventilation in children who are naive to benzodiazepines, or in patients with COPD to avoid the need for ventilation. It is not necessary or appropriate in cases of poisoning to fully reverse the benzodiazepine effect. Flumazenil has a short half-life (about an hour) and in this situation an infusion may therefore be required. Flumazenil is contraindicated when patients have ingested multiple medicines, especially after co-ingestion of a benzodiazepine and a tricyclic antidepressant or any other drug that causes seizures. This is because the benzodiazepine may be suppressing seizures induced by the second drug; its antagonism by flumazenil can reveal severe status epilepticus that is very difficult to control.Contraindications to the use of flumazenil include features suggestive of a tricyclic antidepressant ingestion including a wide QRS, or large pupils. Use in patients postcardiac arrest is also contraindicated.It should be used with caution in patients with a history of seizures, head injury, or chronic benzodiazepine use.Occasionally a respirator may be required but generally few problems are encountered, although behavioral changes are likely in children.If excitation occurs, barbiturates should not be used.Effects of overdose are more severe when taken with centrally-acting drugs, especially alcohol, and in the absence of supportive measures, may prove fatal.
Actavis UK Ltd
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