Benzodiazepine (anxiolytic, sedative, muscle relaxant) Pregnancy: §4.6: The safety of diazepam in human pregnancy has not been established. It SHOULD NOT BE USED in the first and third trimesters (and pregnancy / planning a pregnancy are listed as contraindications in §4.3 unless there are compelling reasons). There may be a small increase in the risk of congenital malformation, particularly oral cleft, with benzodiazepine use in the first trimester, although causality is not established. Administration in the late phase of pregnancy or during labour at high doses can cause hypothermia, hypotonia ('Floppy Infant Syndrome'), heart-rate irregularities, poor suckling and moderate respiratory depression in the neonate; infants of mothers taking benzodiazepines chronically in late pregnancy may develop physical dependency and neonatal withdrawal. Benzodiazepines are found in breast milk and SHOULD NOT be given to breast-feeding mothers.

Diazepam (Anxiolytic/Sedative)

Brand names: Valium, Stesolid

This covers diazepam used as an anxiolytic and sedative - a long-acting benzodiazepine for the short-term relief of severe, disabling anxiety and for short-term sedation.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 5-30 mg daily in divided doses (anxiety states, obsessive-compulsive neuroses and other psychiatric disorders)

Route: Oral

Frequency: In divided doses

Source: UK SPC (eMC) for Diazepam 10 mg Tablet, §4.2 (https://www.medicines.org.uk/emc/product/101913/smpc). DURATION: as an anxiolytic, the lowest dose which can control symptoms should be used; it should not be continued beyond 4 weeks. Long-term chronic use is not recommended. Treatment should always be tapered off gradually — patients who have taken benzodiazepines for a long time may require a longer period during which doses are reduced. Prior to starting treatment a discussion should be held with patients to put in place a strategy for ending treatment, to minimise the risk of dependence, addiction and drug withdrawal syndrome. OTHER ADULT INDICATIONS in this SPC: insomnia associated with anxiety 5-15 mg before bedtime; alcohol withdrawal 5-20 mg, repeated if necessary in 2-4 hours; muscle spasm of varied aetiology, fibrositis, cervical spondylosis 5-15 mg daily in divided doses; cerebral palsy 5-60 mg daily in divided doses; upper motor neurone spasticity 5-60 mg daily in divided doses; adjunct to the management of some types of epilepsy 2-60 mg daily in divided doses (treatment used for as long as the prescriber considers necessary); oral premedication in dental patients 5 mg the night before, 5 mg on waking and 5 mg two hours before the appointment; oral premedication before surgery 5 mg-20 mg. NO SEPARATE MAXIMUM DOSE is stated for the anxiolytic indication — the highest daily figure appearing anywhere in this §4.2 is 60 mg daily in divided doses (cerebral palsy, upper motor neurone spasticity, epilepsy adjunct). ELDERLY AND DEBILITATED PATIENTS: doses should be half the above recommended doses. HEPATIC IMPAIRMENT: use in hepatic impairment may precipitate coma, therefore the dose should be reduced or an alternative drug considered; severe hepatic insufficiency is a contraindication. PAEDIATRIC (fixed mg doses, not per-kg, so not expressed as a structured paedDose): alternative presentations of diazepam are recommended for paediatric usage in order to obtain suitable doses of less than 5 mg; spastic children with minimal brain damage 5-40 mg daily in divided doses; oral premedication before surgery 2 mg-10 mg. Verify any under-18 use against a children's formulary. METHOD OF ADMINISTRATION: for oral administration. Note: §4.5 was not retrieved in this bundle — the interactions listed below are taken from the US label; verify the full UK §4.5.

Dose adjustments

Renal

In severe renal impairment the dose should be reduced (§4.2).

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance, other benzodiazepines or to any of the excipients
Phobic or obsessional states; chronic psychosis; hyperkinesis (paradoxical reactions may occur)
Acute pulmonary insufficiency; respiratory depression; acute or chronic severe respiratory insufficiency (ventilatory failure may be exacerbated)
Myasthenia gravis; sleep apnoea (conditions may be exacerbated)
Severe hepatic insufficiency (elimination half-life may be prolonged); acute porphyria
Should not be used as monotherapy in patients with depression, or those with anxiety and depression, as suicide may be precipitated
Planning a pregnancy; pregnancy (unless there are compelling reasons)

Side effects

Drowsiness (very common); numbed emotions, reduced alertness, fatigue — predominantly at the start of therapy
Ataxia, impaired motor ability, tremor (common); confusion (common); dizziness, headache, concentration difficulties, balance disorders, slurred speech (uncommon)
Anterograde amnesia (uncommon) — may occur at therapeutic dosages, the risk increasing at higher dosages, and may be associated with inappropriate behaviour
Respiratory depression (uncommon); respiratory arrest and increased bronchial secretion (rare); apnoea (not known)
Drug dependence — chronic use even at therapeutic doses may lead to physical and psychic dependence, with withdrawal or rebound phenomena on discontinuation
Increased risk of falls and associated fractures in elderly patients; psychiatric and paradoxical reactions such as excitation, agitation, aggressiveness, hallucinations (rare)

Interactions

Opioids — concomitant use increases the risk of respiratory depression; limit dosage and duration of concomitant use and monitor closely for respiratory depression and sedation (US label)
Centrally acting agents — careful consideration of the pharmacology is required, particularly with phenothiazines, antipsychotics, anxiolytics/sedatives, hypnotics, anticonvulsants, narcotic analgesics, anaesthetics, sedative antihistamines, narcotics, barbiturates, MAO inhibitors and other antidepressants (US label)
Alcohol — concomitant use not recommended due to enhancement of the sedative effect (US label)
Antacids — diazepam peak concentrations are 30% lower when antacids are administered concurrently, although the extent of absorption is unaffected (US label)

Clinical monograph

How it works

It enhances GABA-mediated inhibitory neurotransmission at the GABA-A receptor, producing anxiolytic, sedative, muscle-relaxant and anticonvulsant effects.

Prescribing in practice

Because of the risk of tolerance and dependence, it should be used at the lowest effective dose for the shortest possible time (short-term use only), and longer courses tapered gradually.
Co-administration with opioids, alcohol or other CNS depressants markedly increases the risk of sedation and fatal respiratory depression.
Its long half-life and active metabolites cause accumulation, so use reduced doses and extra caution in the elderly and in hepatic impairment.

Monitoring

Monitor sedation, response, and for signs of tolerance or dependence, reviewing the need to continue at regular intervals.

Counselling the patient

This medicine is for short-term use, as regular use can lead to dependence.
Do not drink alcohol with it, and be aware it can impair driving.
Do not stop it suddenly after prolonged use - it should be reduced gradually.

Evidence & guidelines

NICE and MHRA advise that benzodiazepines such as diazepam be reserved for short-term use because of the risk of dependence and withdrawal.

Reference: NICE CG113 Generalised Anxiety; PHE Alcohol Withdrawal Guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways