What are the best PRN (pro re nata) anxiety medication options in pediatrics?

Best PRN Anxiety Medication Options in Pediatrics

For acute procedural anxiety in pediatric patients, midazolam (intranasal or IV) is the preferred PRN medication, with lorazepam as an alternative for pre-procedure anxiolysis. 1, 2, 3

Context: PRN vs. Chronic Anxiety Treatment

The evidence base for pediatric anxiety treatment overwhelmingly focuses on chronic anxiety disorders (generalized anxiety, social anxiety, separation anxiety, panic disorder), where SSRIs are first-line pharmacotherapy. 1, 4, 5 However, PRN medications serve a fundamentally different purpose: acute situational anxiety relief, particularly for medical procedures. 1

Primary PRN Options for Procedural/Acute Anxiety

Midazolam (First Choice)

Midazolam is the most evidence-supported PRN anxiolytic for pediatric procedural anxiety, available in multiple formulations:

Intranasal Administration

• Dosing: 0.05-0.1 mg/kg initial dose 2, 3
• Advantages: No IV access required, rapid onset, well-tolerated 1
• Considerations: May cause nasal burning; use atomizer for better distribution 1

Intravenous Administration

• Age-specific dosing 2, 3:
  • 6 months to 5 years: 0.05-0.1 mg/kg (total up to 0.6 mg/kg, usually ≤6 mg)
  • 6-12 years: 0.025-0.05 mg/kg (total up to 0.4 mg/kg, usually ≤10 mg)
  • 12-16 years: Dose as adults (total usually ≤10 mg)
• Critical administration: Give over 2-3 minutes, then wait additional 2-3 minutes to evaluate effect before repeating 2, 3
• Titration is essential: Small increments to desired effect prevent oversedation 2, 3

Intramuscular Administration

• Dosing: 0.1-0.15 mg/kg (effective without prolonging emergence) 2, 3
• For more anxious patients: Up to 0.5 mg/kg (total usually ≤10 mg) 2, 3

Safety considerations: Pediatric patients <6 months are particularly vulnerable to airway obstruction and hypoventilation; use smallest increments with careful monitoring. 2, 3 Reduce dose if coadministered with opioids. 2, 3

Lorazepam (Alternative)

Lorazepam provides reliable anxiolysis with anterograde amnesia, particularly useful when preventing recall of unpleasant medical events is desired. 1

• Dosing: 0.02-0.09 mg/kg 1
• Timing: Can be given night before procedure or as oral premedication 1
• Adverse effects: CNS depression (fatigue, drowsiness, ataxia, confusion); rare paradoxical reactions with increased anxiety 1
• Duration: Long-acting; not appropriate for outpatient procedures or hospital stays <72 hours 6

Important Clinical Caveats

What PRN Medications Are NOT Recommended

Benzodiazepines for chronic anxiety disorders lack efficacy evidence in pediatric populations. 5 While midazolam and lorazepam have clear roles for procedural anxiety, randomized controlled trials do not support benzodiazepines for ongoing anxiety disorder management. 5

Hydroxyzine is used in some settings (4% of pediatric antianxiety initiations) but has limited continuation rates (only 19% refill). 7

The SSRI Distinction

SSRIs (fluoxetine, sertraline, fluvoxamine) are NOT PRN medications—they require daily dosing for 6-12 weeks to achieve therapeutic effect. 1, 4, 8, 5 They are first-line for chronic anxiety disorders but irrelevant for acute PRN use. 1, 4, 5

Practical Algorithm for PRN Anxiety in Pediatrics

1. Identify the clinical scenario:

   • Procedural anxiety (IV placement, laceration repair, imaging) → Midazolam preferred 1, 2, 3
   • Pre-procedure anxiolysis with amnesia desired → Lorazepam or midazolam 1
   • Outpatient brief procedure → Intranasal midazolam (no IV needed) 1, 2

2. Age-appropriate dosing:

   • <6 months: Extreme caution, smallest increments, continuous monitoring 2, 3
   • 6 months-5 years: Midazolam 0.05-0.1 mg/kg 2, 3
   • 6-12 years: Midazolam 0.025-0.05 mg/kg 2, 3
   • ≥12 years: Adult dosing protocols 2, 3

3. Route selection:

   • IV access available + need titration → IV midazolam 2, 3
   • No IV access + cooperative patient → Intranasal midazolam 1, 2
   • Pre-procedure (night before/morning of) → Oral lorazepam or IM midazolam 1, 2, 3

4. Monitoring requirements:

   • Continuous observation for respiratory depression 2, 3
   • Pulse oximetry and airway equipment immediately available 1
   • Reduce doses if opioids coadministered 2, 3

Common Pitfalls to Avoid

• Rapid IV bolus of midazolam: Always administer over 2-3 minutes and wait additional 2-3 minutes before redosing 2, 3
• Using lorazepam for outpatient procedures: Its long duration (requires 72+ hour hospitalization consideration) makes it inappropriate 6
• Prescribing SSRIs as PRN: These require weeks of daily dosing and are not acute anxiolytics 1, 4, 8
• Inadequate monitoring in <6 month olds: This age group has highest risk of airway complications 2, 3