What is the recommended initial dose of Ativan (lorazepam) for intravenous administration for anxiety or procedural sedation?

Recommended Dosing for Intravenous Lorazepam (Ativan)

For adult patients requiring intravenous lorazepam for anxiety or procedural sedation, the recommended initial dose is 2 mg total (or 0.02 mg/lb, whichever is smaller), administered slowly over 1-2 minutes. 1

Initial Dosing Guidelines

• The standard initial IV dose for adult patients is 2 mg, which is sufficient for sedating most adult patients 1
• For elderly patients (over 50 years), this 2 mg dose should ordinarily not be exceeded 1
• When greater amnesia for perioperative events is desired, doses up to 0.05 mg/kg to a maximum of 4 mg may be administered 1
• Administration rate should not exceed 2 mg per minute to minimize adverse effects 1

Dose Adjustments for Special Populations

• For elderly patients, reduce the dose by 20% or more due to reduced clearance 2
• No dosage adjustments are needed for patients with hepatic disease for acute dose administration 1
• For patients with renal disease, no adjustment is needed for acute dosing, but caution should be exercised if frequent doses are given over short periods 1
• Reduce lorazepam dose by 50% when coadministered with probenecid or valproate 1

Administration Considerations

• Prior to IV use, lorazepam injection must be diluted with an equal volume of compatible solution (Sterile Water for Injection, Sodium Chloride Injection, or 5% Dextrose Injection) 1
• Mix thoroughly by gently inverting the container repeatedly until a homogenous solution results 1
• Do not shake vigorously as this will result in air entrapment 1
• When properly diluted, inject directly into a vein or into the tubing of an existing IV infusion 1

Monitoring and Safety

• Monitor oxygen saturation and respiratory effort during administration 3
• Be prepared to support ventilation if needed, as there is an increased incidence of apnea when lorazepam is given rapidly IV or when combined with other sedative agents 3
• Respiratory depression is more likely in patients with underlying respiratory disease or when lorazepam is combined with opioids 3, 2
• Flumazenil may be administered to reverse life-threatening respiratory depression, but it will also counteract any anticonvulsant effects 3

Clinical Considerations

• Lorazepam has a longer duration of action (1-24 hours) compared to midazolam (1-4 hours) 3
• For procedural sedation, lorazepam should be administered 15-20 minutes before the anticipated procedure for optimal effect 1
• In critically ill patients, maintenance doses of 0.02±0.01 mg/kg/hr have been shown to achieve desired sedation levels 4
• Lorazepam has been found to be more cost-effective than midazolam or propofol for sedation in critically ill patients, though oversedation may be more common 4

Common Pitfalls to Avoid

• Underdosing in status epilepticus situations (though this is a different indication than anxiety/procedural sedation) has been associated with progression to refractory status epilepticus 5
• Avoid rapid administration, which can increase risk of respiratory depression 1
• Be cautious with concomitant use of other CNS depressants, as this increases risk of respiratory depression 3
• Monitor for delayed awakening after discontinuation, especially with prolonged infusions 6

Remember that these dosing recommendations are specifically for anxiety or procedural sedation. Different dosing regimens apply for other indications such as status epilepticus.