What is the dose of Lorazepam (a benzodiazepine) for an acute seizure?

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From the Guidelines

Lorazepam Dosing for Acute Seizures

Lorazepam is administered at a dose of 0.05-0.10 mg/kg (maximum: 4 mg per dose) intravenously for the management of acute seizures, which may be repeated every 10-15 minutes if seizures persist 1.

Key Considerations

  • The dose may vary depending on the specific clinical context, such as the severity of the seizure and the patient's response to treatment.
  • It is essential to monitor oxygen saturation and be prepared to provide respiratory support, as there is an increased incidence of apnea when lorazepam is combined with other sedative agents 1.
  • Flumazenil may be administered to reverse life-threatening respiratory depression caused by lorazepam; however, it will also counteract the anticonvulsant effects and may precipitate recurrence of seizures 1.

Administration Guidelines

  • Intravenous administration should be done slowly over 2-4 minutes to minimize the risk of adverse effects.
  • In patients with recurrent or prolonged seizures, a continuous infusion of lorazepam may be considered, with a dose range of 0.05-0.10 mg/kg (maximum: 1 mg) intravenously every 8 hours for 3 doses, as maintenance doses after resolution of status epilepticus 1.

Clinical Context

The management of acute seizures requires careful consideration of the patient's overall clinical context, including their medical history, current medications, and potential allergies. It is crucial to follow established guidelines and consult with a healthcare professional to ensure the safe and effective use of lorazepam for acute seizure management.

From the FDA Drug Label

For the treatment of status epilepticus, the usual recommended dose of lorazepam injection is 4 mg given slowly (2 mg/min) for patients 18 years and older. If seizures cease, no additional lorazepam injection is required If seizures continue or recur after a 10- to 15-minute observation period, an additional 4 mg intravenous dose may be slowly administered.

The dose of Lorazepam for an acute seizure (status epilepticus) is 4 mg given slowly (2 mg/min) for patients 18 years and older, with the option to administer an additional 4 mg dose if seizures continue or recur after a 10- to 15-minute observation period 2.

From the Research

Dose of Lorazepam for Acute Seizure

The dose of lorazepam for an acute seizure can vary depending on the patient's age, weight, and the specific clinical scenario.

  • For children, a dose of 0.1 mg/kg (maximum 4 mg) is used, as seen in a study comparing intranasal versus intravenous lorazepam for control of acute seizures in children 3.
  • For adults, a dose of 2-8 mg/70kg is recommended as initial treatment for status epilepticus 4.
  • In another study, lorazepam 4 mg for adults (age, 16 years old or older) or 0.05mg/kg for children (age, 3 months to less than 16 years) was administered as a slow intravenous injection for status epilepticus or repetitive seizures 5.
  • Sublingual lorazepam oral concentrate solution has also been used as acute treatment for adults with prolonged and repetitive seizures, with a median dose of 1 mg (range 0.5 to 2 mg) 6.

Administration Routes

Lorazepam can be administered through various routes, including:

  • Intravenous (IV) 3, 5, 4
  • Intranasal (IN) 3
  • Sublingual 6
  • Rectal diazepam gel is also used for acute repetitive seizures, but lorazepam is not typically administered rectally 7.

Efficacy and Safety

The efficacy and safety of lorazepam for acute seizures have been evaluated in several studies.

  • A study found that intranasal administration of lorazepam is not inferior to intravenous administration for termination of acute convulsive seizures in children 3.
  • Another study reported that the proportion of patients whose initial seizure stopped within 10 minutes and who continued seizure-free for at least 30 minutes after the completion of initial dose was 48.0% (12/25) 5.
  • Sublingual lorazepam solution has been shown to be effective for interrupting prolonged and repetitive seizures, with 66% (23/35) of patients with repetitive seizures reporting no further seizure activity after administering treatment, and 70% (7/10) with prolonged seizures reporting seizure activity ceased within 5 minutes of treatment 6.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Management of status epilepticus.

Critical care and resuscitation : journal of the Australasian Academy of Critical Care Medicine, 1999

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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