Can lorazepam (Ativan) be given intramuscularly (IM) if intravenous (IV) access is not available?

Intramuscular Lorazepam Administration When IV Access Is Unavailable

Yes, lorazepam can be given intramuscularly (IM) when intravenous (IV) access is not available, though it is not the preferred route for certain indications like status epilepticus. The FDA-approved drug labeling specifically addresses this administration route with clear guidelines.

Administration Guidelines for IM Lorazepam

Status Epilepticus

• While IV administration is preferred for status epilepticus, the FDA label explicitly states that "when an intravenous port is not available, the IM route may prove useful" 1
• The therapeutic levels may not be reached as quickly with IM administration compared to IV administration 1
• IM lorazepam should be injected deep in the muscle mass, undiluted 1

Preanesthetic Use

• For preanesthetic sedation: 0.05 mg/kg up to a maximum of 4 mg IM 1
• Should be administered at least 2 hours before the anticipated procedure for optimal effect 1

Anxiety and Sedation

• For treatment of alcohol withdrawal syndrome: 1-4 mg IM every 4-8 hours 2
• For acute anxiety: Similar dosing to IV (typically 0.05-0.1 mg/kg) may be used

Clinical Considerations

Advantages of IM Administration

• Provides an alternative route when IV access is difficult or impossible
• Can be administered more quickly than establishing IV access in emergency situations
• A 2012 study showed that intramuscular midazolam (another benzodiazepine) was at least as effective as IV lorazepam for prehospital seizure cessation, with faster overall treatment times 3

Limitations

• Slower onset of action compared to IV administration
• May have less predictable absorption compared to IV route
• Not the preferred route for status epilepticus but remains a viable alternative when IV access is unavailable 1, 4

Special Populations

• No dosage adjustments needed for elderly patients or those with hepatic disease 1
• For patients with renal disease, caution should be exercised if frequent doses are given over relatively short periods 1
• Safety not established in pediatric patients; use not recommended in patients under 18 years 1

Alternative Routes When IV Access Is Unavailable

When IV access is unavailable, consider these alternatives based on the clinical situation:

1. Intramuscular lorazepam - viable but not preferred for status epilepticus 1
2. Buccal or intranasal midazolam - effective alternatives for acute seizures 5
3. Rectal diazepam - another option for seizure management 6

Potential Adverse Effects

• Respiratory depression (most common serious side effect)
• Sedation
• Hypotension
• Risk of dependence with prolonged use

Key Practice Points

• Always have equipment to maintain a patent airway immediately available before administering lorazepam by any route 1
• Monitor vital signs, particularly respiratory status, after administration
• When given intramuscularly, lorazepam can be used with atropine sulfate, narcotic analgesics, and other commonly used medications 1
• Consider dose reduction (50%) when coadministered with probenecid or valproate 1

Remember that while IM lorazepam is an acceptable alternative when IV access is unavailable, establishing IV access remains the preferred approach whenever possible, particularly for status epilepticus.