What is a reasonable PRN (pro re nata, as needed) medication option for a patient admitted with anxiety, specifically using Ativan (lorazepam)?

PRN Lorazepam for Anxiety During Hospital Admission

For patients admitted with anxiety, lorazepam 0.5-1 mg orally every 4 hours PRN is the recommended dosing regimen, with a maximum of 4 mg in 24 hours for most adults. 1

Dosing Considerations

Standard Adult Dosing

• Initial dose: 0.5-1 mg orally every 4 hours as needed
• Maximum daily dose: 4 mg in 24 hours
• Route: Oral (tablets can also be used sublingually if needed) 1

Special Populations

• Elderly or debilitated patients: Reduce dose to 0.25-0.5 mg with a maximum of 2 mg in 24 hours 1
• Patients with renal impairment: Consider dose reduction if eGFR <30 mL/min 1
• Patients unable to swallow: Consider alternative benzodiazepine options such as midazolam 2.5-5 mg subcutaneously every 2-4 hours as needed 1

Clinical Implementation

First-line Approach

1. Identify and address underlying causes of anxiety before medication administration
2. Try non-pharmacological interventions first:
   • Ensure effective communication and orientation
   • Provide adequate lighting
   • Explore patient concerns and anxieties 1

Monitoring and Follow-up

• Assess response 30-60 minutes after administration
• Monitor for excessive sedation, respiratory depression, and paradoxical reactions
• Reassess need for continued PRN medication daily
• Avoid prolonged use beyond 4 months due to risk of dependence 2

Important Considerations and Cautions

Contraindications

• Severe respiratory insufficiency
• Severe hepatic disease
• Myasthenia gravis
• Known hypersensitivity to benzodiazepines 2

Warnings

• Risk of dependence: Physical dependence can develop with regular use
• Withdrawal risk: Do not discontinue abruptly after regular use
• Respiratory depression: Caution in patients with compromised respiratory function
• CNS depression: Avoid concurrent use with other CNS depressants including opioids and alcohol 2

Drug Interactions

• Increased sedation when combined with:
  • Opioids
  • Antipsychotics
  • Other sedatives
  • Alcohol 2

Alternative Options

If lorazepam is contraindicated or ineffective, consider:

1. For anxiety without delirium:

   • Non-benzodiazepine anxiolytics (e.g., buspirone)
   • SSRIs for longer-term management 3

2. For anxiety with agitation or delirium:

   • Haloperidol 0.5-1 mg orally at night and every 2 hours as needed
   • Quetiapine 25 mg orally at bedtime (especially in elderly) 1

Practical Application

• Document baseline anxiety level before administration
• Evaluate and document response after administration
• If patient requires frequent dosing (more than twice daily), consider scheduled dosing or alternative treatments 1
• For patients with anticipated prolonged anxiety, consider initiating an SSRI for long-term management while using lorazepam for acute symptoms 3

Remember that while lorazepam is effective for short-term management of anxiety symptoms during hospitalization, it should be used for the shortest duration possible to minimize risks of dependence and adverse effects.