midazolam hydrochloride: clinical use

Prescribing considerations

• Use injectable midazolam only where respiratory and cardiovascular function can be continuously monitored and supported, with trained resuscitation personnel available.
• Individual sensitivity varies. Older, debilitated or chronically ill patients and those with respiratory, cardiac, renal or hepatic impairment are at increased risk of prolonged or profound effects.
• Review opioids, other CNS depressants and CYP3A inhibitors or inducers before administration.
• Prolonged use can cause tolerance and physical dependence; abrupt withdrawal after extended infusion may cause withdrawal symptoms, including seizures.

Contraindications and cautions

• Hypersensitivity to midazolam, another benzodiazepine or a formulation excipient.
• Selected injection products: conscious sedation in severe respiratory failure or acute respiratory depression.
• Selected oromucosal product: myasthenia gravis, severe respiratory insufficiency, sleep apnoea syndrome or severe hepatic impairment.

Monitoring

• Respiratory rate, oxygen saturation, airway patency, blood pressure, pulse and depth of sedation.
• Delayed recovery or respiratory depression where CYP3A inhibition, organ impairment or prolonged administration may cause accumulation.
• Paradoxical agitation or behavioural reactions, particularly in children and older people.
• After prolonged administration, dependence and withdrawal risk during discontinuation.

Clinical pharmacology

A short-acting imidazobenzodiazepine and positive allosteric modulator of GABA-A receptors. It is primarily metabolised through CYP3A pathways; active metabolite accumulation can contribute to prolonged sedation, particularly in critical illness or renal impairment.

Formulation and product differences

• Oromucosal solution is supplied in a needle-free, pre-filled oral syringe for emergency seizure treatment and must not be injected.
• Injection and infusion products are for administration by trained professionals; permitted routes and compatible infusion fluids are product-specific.
• Selected injectable presentations differ in container type, storage, dilution compatibility and in-use stability; consult the relevant SmPC before preparation.

Oromucosal preparation

Route: Oromucosal

Strengths: 2.5 mg, 5 mg, 7.5 mg, 10 mg

Injection

Route: Parenteral

Strengths: 1 mg/1 mL, 1 mg/mL, 2 mg/mL, 5 mg/mL