Can lorazepam be given in 5 ml of sterile water for IV administration?

Lorazepam IV Administration in Sterile Water

Lorazepam for IV administration should NOT be diluted in 5 mL of sterile water, as this exceeds the recommended solubility parameters and may lead to precipitation of the medication. 1

Proper Dilution Guidelines for IV Lorazepam

Lorazepam injection must be properly diluted prior to intravenous administration according to the following guidelines:

• Lorazepam must be diluted with an equal volume of compatible solution immediately prior to IV use 1
• Compatible solutions for dilution include:
  • Sterile Water for Injection, USP
  • Sodium Chloride Injection, USP
  • 5% Dextrose Injection, USP 1

Mixing Instructions

1. Dilute with an equal volume of compatible solution
2. Mix thoroughly by gently inverting the container repeatedly until a homogenous solution results
3. Do not shake vigorously (will result in air entrapment)
4. Administer at a rate not exceeding 2 mg per minute 1

Solubility Considerations

The solubility of lorazepam in various solutions is limited:

• In sterile water: 0.054 mg/mL
• In 5% dextrose: 0.062 mg/mL
• In 0.9% sodium chloride: 0.027 mg/mL 2

This limited solubility means that attempting to dissolve lorazepam in 5 mL of sterile water would likely result in precipitation and potentially ineffective medication delivery, which could be critical in emergency situations like status epilepticus.

Stability Concerns

Lorazepam diluted in bacteriostatic water for injection has poor stability:

• After 7 days' storage, concentration drops to 88% at room temperature and 90% at refrigerated temperature
• After 2 weeks, concentration dramatically decreases to 42% at room temperature and 1.5% at refrigerated temperature
• Crystals appear after 2-4 weeks of storage 3

Clinical Implications

For status epilepticus, proper administration is critical:

• The recommended dose is 0.05-0.10 mg/kg IV (maximum: 4 mg per dose) 4
• Underdosing lorazepam in status epilepticus significantly increases the risk of progression to refractory status epilepticus 5
• Improper dilution could result in underdosing due to precipitation

Practical Administration Tips

• Always inspect parenteral drug products visually for particulate matter and discoloration prior to administration 1
• Do not use if solution is discolored or contains a precipitate 1
• For optimal effect in status epilepticus, administer slowly over 2-3 minutes to minimize respiratory depression 6
• Monitor oxygen saturation and be prepared to provide respiratory support, as there is an increased risk of apnea when combined with other sedative agents 4

Conclusion

For safe and effective IV administration of lorazepam, follow the FDA-approved dilution instructions using equal volumes of lorazepam and compatible solution. Using 5 mL of sterile water alone for dilution is not recommended due to solubility limitations and risk of precipitation.