Lorazepam
Description
Lorazepam is a benzodiazepine sedative used for reduction of anxiety or as an adjunct for anesthesia.
Indications
- Anxiety disorders (only up to 4 months, to minimize chances of dependency)
- Anxiety-related insomnia
- Anesthesia premedication to relieve anxiety or induce sedation and amnesia
- Status epilepticus
- Rapid tranquilization of agitated patients
- Alcohol withdrawal
- Panic disorder
- Delirium
- Chemotherapy-associated nausea
- Psychogenic catatonia
Administration Routes
Side Effects
- Local injection site reaction
- Ataxia
- Dizziness
- Respiratory depression
- Paradoxical reaction
- Confusion
- Seizures
- Tachycardia
- Hypotension
- Fainting
- Withdrawal symptoms if abruptly discontinued after long-term use
- Cognitive deficits
- Behavioral changes
- Difficulty speaking clearly
- Constipation
Dosage
For anxiety disorder:
- 30 to 45 μg/kg orally, up to 3 times daily
For insomnia:
- 10 to 30 μg/kg orally at bedtime
Premedication for anesthesia:
- 50 μg/kg IM administered 2 hours before surgery
- or, 45 μg/kg IV administered 15 to 20 minutes before surgery
For status epilepticus:
- 100 μg/kg over at least 1 minute
- dose may be repeated every 5 to 10 minutes as needed
- must be diluted with an equal volume of saline (1:1 dilution)
For agitation / delirium:
- loading dose is 20 to 40 μg/kg IV bolus
- maintenance dosage is either:
- 20 to 60 μg/kg IV bolus every 2 to 6 hours as needed, or infusion of 10 to 100 μg/kg/h
For alcohol withdrawal syndrome:
- dose according to symptoms
- 30 μg/kg oral, IM, or IV every 6 hours as needed for the first 24h
- 15 μg/kg oral, IM, or IV every 6 hours as needed for another 24h
For chemotherapy-associated nausea:
- 15 to 30 μg/kg oral or IV, every 6 hours
For psychogenic catatonia:
- 15 to 30 μg/kg orally, IM, or IV, administered daily
- initial dose can be repeated after 3 hours up to two additional times if the initial dose is ineffective
- continuing treatment can be titrated as necessary for symptoms up to a maximum of 120 μg/kg daily, with treatment continuing for up to 5 days.
Available forms
- 0.1 mg tablet
- 0.25 mg tablet
- 0.5 mg tablet
- 1 mg tablet
- 1 mg extended-release tablet
- 0.25 mg/mL oral solution
- 0.5 mg/mL injection solution
- 1 mg/mL injection solution
Pharmacokinetics
| Route | Absorption Half-Life | Onset | Peak | Elimination Half-Life | Duration of action |
|---|---|---|---|---|---|
| IV | 5 min | 1-5 mins | Immediate | 12-18 hrs | 12-24 hrs |
| IM | 15-20 mins | 15-30 mins | 60-90 mins | ||
| O | 30 mins | 20-30 mins | 2 hrs | 6-8 hrs |
Oral bioavailability: 90%
Interactions
TODO