Please check your internet connection and try again.
# Lorazepam
## Overview
Lorazepam is a benzodiazepine with anxiolytic, sedative, hypnotic, amnestic, anticonvulsant, and muscle relaxant properties. It acts by enhancing the effect of the neurotransmitter gamma-aminobutyric acid (GABA) at the GABA$_{\text{A}}$ receptor, resulting in increased chloride ion conductance and hyperpolarization of the neuron.
## Primary Indications
* Anxiety disorders
* Insomnia due to anxiety or transient situational stress
* Status epilepticus
* Preoperative sedation and anxiolysis
* Management of alcohol withdrawal syndrome
## Adult Dosing
* **Anxiety:** 1-4 mg orally every 6-8 hours. Maximum dose generally 10 mg/day.
* **Insomnia:** 2-4 mg orally at bedtime.
* **Status Epilepticus:** 4 mg intravenously (IV) or intramuscularly (IM). Repeat in 5-10 minutes if needed, to a maximum of 8 mg in a 12-hour period.
* **Preoperative Sedation:** 2-4 mg IM 2 hours before surgery, or 2 mg IV 15-30 minutes before induction.
Dosing for specific indications, particularly IV/IM, may vary based on institutional protocols.
## Pediatric Dosing
Pediatric dosing data for lorazepam is limited and often requires careful consideration of weight, age, and clinical indication. Dosing should be individualized and initiated at the lower end of the adult range or based on specific pediatric protocols.
* **Status Epilepticus (IV):** 0.1 mg/kg to a maximum of 4 mg per dose. May be repeated once after 10-15 minutes if seizures persist.
* **Sedation:** Dosing is highly variable and dependent on the procedural sedation protocol.
## Dose Adjustments
* **Hepatic Impairment:** Use with caution; dose reduction may be necessary.
* **Renal Impairment:** No specific dose adjustment is routinely recommended, but monitor for increased CNS effects.
* **Elderly:** Start with lower doses (e.g., 1-2 mg/day) and titrate slowly due to increased sensitivity to CNS effects.
## Contraindications
* Known hypersensitivity to benzodiazepines or any component of the formulation.
* Acute narrow-angle glaucoma.
* Severe respiratory insufficiency.
* Severe hepatic insufficiency.
* Myasthenia gravis.
* Careful consideration in patients with sleep apnea.
## Adverse Effects
* **Common:** Sedation, dizziness, weakness, ataxia, fatigue.
* **Less Common:** Blurred vision, confusion, depression, anterograde amnesia, paradoxical reactions (e.g., agitation, excitement).
* **Rare:** Respiratory depression, hypotension, paradoxical excitation.
## Key Drug Interactions
* **CNS Depressants (e.g., opioids, alcohol, antihistamines, antipsychotics):** Additive CNS depression, increased risk of sedation, respiratory depression, and coma. Co-administration of lorazepam and opioids significantly increases the risk of respiratory depression, sedation, coma, and death.
* **CYP Inhibitors/Inducers:** Lorazepam is primarily metabolized by glucuronidation, not CYP enzymes, so interactions with CYP inhibitors/inducers are less likely compared to other benzodiazepines.
* **Valproic acid:** May increase lorazepam plasma concentrations.
## Monitoring
* Sedation level, respiratory rate, and blood pressure, especially after IV administration.
* Signs of dependence and withdrawal upon discontinuation.
* Effectiveness for the intended indication.
## Clinical Pearls
* Lorazepam has a relatively long half-life, but its effects can be profound.
* Avoid abrupt discontinuation to prevent withdrawal symptoms. Tapering of the dose is recommended.
* IM absorption can be unpredictable; IV administration is preferred for acute situations when feasible.
* Tolerance can develop with chronic use, requiring dose escalation.
* Paradoxical reactions are more common in children and the elderly.
***
**Disclaimer:** This information is intended for clinical pharmacists and healthcare professionals. It is not a substitute for professional medical advice. Always consult the most current prescribing information and institutional guidelines before making any treatment decisions.
