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Benzodiazepine (long-acting) Pregnancy: Should not be used during pregnancy, especially the first and last trimester, unless the clinical condition of the woman requires it; chlordiazepoxide crosses the placenta and animal studies have shown reproductive toxicity. High doses or prolonged low doses in the last trimester or during labour may produce foetal heart-rate irregularities, moderate respiratory depression, hypotonia, poor sucking and neonatal hypothermia, with a risk of neonatal withdrawal after chronic maternal use. Avoid during breast-feeding if possible. Because of genotoxic potential, women of childbearing potential should use effective contraception during treatment and for 7 months afterwards, and men should use effective contraception and not father a child during treatment and for 4 months afterwards (SPC 4.6).

Chlordiazepoxide

Brand names: Librium

Chlordiazepoxide is a long-acting benzodiazepine used mainly for the management of acute alcohol withdrawal and, less commonly, for short-term relief of anxiety.

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: 10 mg (anxiety states, usual dose); 20 mg for severe symptoms
Route: Oral
Frequency: 10 mg 2-3 times a day (up to 30 mg daily in divided doses); for severe symptoms 20 mg 2-4 times a day
Max: Up to 100 mg daily in divided doses
Source product is Librium 10 mg Capsules (chlordiazepoxide hydrochloride). Dose adjusted on an individual basis. Anxiety states: duration of treatment should generally not be more than 4 weeks, including a tapering-off process. Insomnia associated with anxiety: 10-30 mg before retiring; duration generally a few days to two weeks, maximum four weeks including tapering. Symptomatic relief of acute alcohol withdrawal: 25-100 mg, repeated if necessary in 2 to 4 hours. Muscle spasm of varied aetiology: 10-30 mg daily in divided doses. Elderly or debilitated patients, patients with organic brain damage, respiratory impairment and/or hepatic or renal dysfunction should normally not exceed half of the doses normally recommended; use the lowest dose that controls symptoms. Chlordiazepoxide is a long-acting benzodiazepine - monitor regularly at the start of treatment and reduce dose or frequency if needed to prevent overdose due to accumulation. Treatment should not be continued at the full dose beyond four weeks and should always be tapered off gradually; long-term chronic use is not recommended. If used for epilepsy, use for as long as the prescriber considers necessary. Paediatric: Librium is not for paediatric use. Capsules must be taken with water and not chewed. eMC section 4.5 was not captured in this bundle (section 4.4 truncated at the source-fetch limit), so no interaction list is given.

Dose adjustments

Renal

Patients with hepatic or renal dysfunction (and elderly or debilitated patients, organic brain damage, respiratory impairment) should normally not exceed half of the doses normally recommended (SPC 4.2).

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Hypersensitivity to chlordiazepoxide or any of the excipients
  • Myasthenia gravis
  • Severe pulmonary insufficiency
  • Respiratory depression
  • Severe hepatic insufficiency
  • Sleep apnoea syndrome
  • Phobic or obsessional states
  • Chronic psychosis
  • Spinal or cerebral ataxia

Side effects

  • Drowsiness, sedation, somnolence and fatigue - dose-related and may persist into the following day even after a single dose (common)
  • Dizziness, unsteadiness, ataxia, balance disorder and confusional states (common); elderly are particularly sensitive and may become confused
  • Falls and consequent fractures in the elderly due to the myorelaxant effect; muscle weakness
  • Respiratory depression (frequency not known); hypotension (rare)
  • Urinary retention and incontinence (rare); visual impairment including diplopia (rare)
  • Drug dependence, paradoxical drug reactions (anxiety, insomnia, agitation, aggression, suicidal ideation) and drug withdrawal symptoms
  • Rare bone marrow depression (thrombocytopenia, leukopenia, agranulocytosis, pancytopenia); jaundice and raised transaminases (frequency not known)

Clinical monograph

How it works

It potentiates the inhibitory neurotransmitter GABA at the GABA-A receptor, producing anxiolytic, sedative and anticonvulsant effects.

Prescribing in practice

  • In alcohol withdrawal it is usually given as a reducing regimen; combined with continued alcohol or opioids it can cause dangerous respiratory depression.
  • Tolerance and dependence occur with prolonged use, so treatment should be short and tapered.
  • Reduce the dose and use caution in the elderly and in hepatic impairment, where accumulation can precipitate encephalopathy.

Monitoring

Monitor withdrawal severity, conscious level and respiratory status during treatment rather than by routine bloods.

Counselling the patient

  • Do not drink alcohol while taking this medicine.
  • It may cause drowsiness; do not drive if affected.
  • Take it exactly as the reducing schedule directs and do not stop suddenly.

Evidence & guidelines

Benzodiazepines such as chlordiazepoxide are recommended by NICE for medically assisted alcohol withdrawal.

Reference: SmPC Librium; NICE CG100 (Alcohol-Use Disorders Diagnosis 2010); NICE CG115 (Alcohol-Use Disorders Management); SIGN 156; 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).

Related

Curated clinical cross-links plus same-class fallbacks.