Midazolam

See critical care quick reference for drug doses by weight.

General

• Type: Benzodiazepines
• Dosage Forms: IV
• Common Trade Names: Versed

Adult Dosing

• Anxiolysis/sedation:
  • 1-2mg IV push
  • 0.07 to 0.08 mg/kg IM, usual dose 5 mg for 60 kg pt
• ICU Sedation:
  • Load: 10-50mcg/kg IV infusion
  • Maintenance: 20-100 mcg/kg/hr infusion
  • Use with standardized sedation protocol for titration

Pediatric Dosing

See critical care quick reference for drug doses by weight.

• Anxiolysis/sedation:
  • 6mo-5yr: 0.05-0.1 mg/kg IV push
  • 6-12yr: 0.025-0.05 mg/kg IV push

• Intranasal
  • Seizure: 0.2 mg/kg IN divided between nostrils
  • Procedural sedation: 0.2-0.6 mg/kg IN divided between nostrils

Special Populations

• Pregnancy Rating: D
  • Maternal use shortly before delivery associated with floppy infant syndrome
• Lactation: Distributed in breast milk, use with caution
• Renal Dosing:
  • Adult: Decrease by 50% for severe renal failure
  • Pediatric
• Hepatic Dosing:
  • Adult: Prolonged clearance in cirrhosis
  • Pediatric

Contraindications

• Allergy to class/drug

Adverse Reactions

Serious

• Apnea
• Hypopnea
• Hypotension
• Delirium, when used for prolonged periods in ICU setting

Common

• Drowsiness
• Nausea/vomiting

Pharmacology

• Peak effect:
  • IM: Children: 15 to 30 minutes; Adults: 30 to 60 minutes
  • IV: 5 to 7 minutes
  • Intranasal: 10 minutes
• Duration
  • IV: Single dose: <2 hours (dose-dependent),up to 6 hours w/ cirrhosis
  • IM: Up to 6 hours; Mean: 2 hours
  • Intranasal: Children: 18 to 41 minutes
• Half-life: 1.8-6.4 hr
• Metabolism: Metabolized in liver by CYP3A4 to active metabolite alpha1-hydroxymidazolam
• Excretion: Renal
• Mechanism of Action: CNS depressant. Acts at GABA receptor to increase frequency of chloride channel opening, causing hyperpolarization and stabilization of neuronal membrane.

See Also

• Intranasal sedation

References

Micromedex

Authors

Ross Donaldson