Lorazepam Intravenous for Adults

Who can administer

Status epilepticus: may be administered by registered competent doctor or nurse/midwife.

Other indications: Restricted administration: see appendix 1

Important information

• Generalised convulsive status epilepticus may be defined as" 5 or more minutes of continuous seizure activity, OR more than one seizure without recovery in between" ^{(ref 1)}

Available preparations

Ativan 4mg per 1mL ampoule (currently in short supply)

Lorazepam 4mg per 1mL ampoule (Macure)

Reconstitution

Already in solution

• Draw up using a 5 micron filter needle
• Dilute further prior to administration

Methods of intravenous administration

Slow intravenous injection

• Dilute with an equal volume of either Sodium chloride 0.9% or Water for Injections immediately before administration (example add 1mL injection solution to 1mL diluent)
• Inject into a large vein at a rate no faster than 2mg/minute, except in the control of status epilepticus where rapid injection is required ^{(ref 2)}

Infusion

• Not recommended, see further information.

Dose in adults

Premedication

• Administer 50 micrograms/kg (0.05mg/kg) given 30 to 45 minutes before surgery ^{(ref 3)}

Convulsive status epilepticus (see important information for definition)

• Administer 4mg
• Allow a few minutes (e.g.three to five minutes) to assess its effect before deciding whether additional doses are necessary ^{(ref 1)}
• Elderly and debilitated patients may respond to lower doses

Acute anxiety ^{(ref 3)}

• Administer 25 to 30 micrograms per kg (0.025 to 0.03mg/kg) (1.8 to 2.1mg for 70kg patient)
• Can repeat if required after six hours

Elderly and debilitated

• May respond to lower doses - half dose may be sufficient

Renal and hepatic impairment

• Contraindicated in severe hepatic impairment
• Patients with renal impairment have increased cerebral sensitivity to lorazepam ^{(ref 3)}
• Start with small doses in severe renal impairment
• Monitor frequently and adjust dose carefully according to patient response in both renal and hepatic impairment

Further information

• Administration by infusion is an unlicensed method of administration and is NOT recommended at GUH, as precipitation has been reported, particularly with the 4mg per 1mL formulation.

Storage

• Store between 2 to 8⁰C

References

SPC Lorazepam (Macure) 26th Nov 2021

1: Convulsive status epilepticus in adults: Classification, clinical features and diagnosis UpToDate monograph. downloaded 16th Feb 2022

2: Injectable Medicines Guide Medusa, downloaded 16th Feb 2022

3: BNF, accessed online 16th Feb 2022

Therapeutic classification

Benzodiazepine