Lorazepam: Uses, Dosage, and Side-Effects

Lorazepam is a drug widely used in the treatment of certain clinical conditions. In this article, we analyze what it's prescribed for, the recommended doses, and the most frequent side effects.
Lorazepam: Uses, Dosage, and Side-Effects

Last update: 19 July, 2022

Lorazepam is a benzodiazepine. It’s used as a sedative and anxiolytic in the clinical setting due to its rapid onset of action (1 to 3 minutes, intravenously). This drug is considered high potency and shows short-acting characteristics (Griffin, 2013).

Its mechanism of action focuses on the benzodiazepine receptors on postsynaptic neurons, more specifically on gamma-aminobutyric acid (GABA), at various sites in the central nervous system (CNS).

Lorazepam enhances the inhibitory effects of GABA. This increases the conductivity of chloride ions in cells (Ghiasi, Bhansali, & Marwaha, 2020).

GABA is one of the main inhibitory neurotransmitters. In other words, it reduces the activity of the cells (neurons) of the central nervous system. It’s found at high levels in the cortex and the limbic system. When its inhibitory action occurs at the limbic level, more specifically in the amygdala, it helps in anxiety disorders. On the other hand, when its inhibitory activity occurs in the cortex, it helps in seizure disorders.

Lorazepam pot

Uses of lorazepam

This medicine is used to treat various problems, as detailed in the following list (Ghiasi, Bhansali, and Marwaha, 2020).

  • Anxiety disorders. The starting dose is two mg to three mg orally which can be repeated two to three times a day. The maximum dose is ten mg per day.
  • Insomnia due to anxiety or stress. In patients under 65 years of age, a dose of 0.5 to two mg is recommended at bedtime. In patients over 65 years, the suggested dose is 0.5 to one mg at bedtime.
  • Psychogenic catatonia. For this problem, the dose is one mg to two mg intramuscularly. The dose can be repeated in three hours and then again in another three hours if the initial and subsequent doses are ineffective.
  • Agitation in the intensive care unit (ICU) patient. The intravenous dose for agitation is 0.02 to 0.04 mg/kg (maximum single dose of two mg). To maintain it, a dose of 0.02 to 0.06 mg/kg is recommended every two to six hours as needed.
  • Status epilepticus. Intravenously, the dose is 0.1 mg/kg (maximum dose of four mg), at a maximum rate of two mg per minute. It can be repeated after five to ten minutes.
  • Alcohol withdrawal delirium. Intravenously, a dose of one to four mg every five to 15 minutes is recommended until the patient is calm. This can be repeated every hour, as needed. For intramuscular administration, a dose of one to four mg every 30 to 60 minutes is suggested until the person calms down.

Lorazepam dosage

As we’ve mentioned already, the doses of lorazepam vary according to the problem for which it’s being used. Usually, the onset of action of these doses is between one to three minutes if administered intravenously and 15 to 30 minutes if administered intramuscularly.

Next, we’ll review the recommended doses for anxiety based on age and oral dosage.

For the oral solution dosage form

  • From 12 years of age. Two to six milligrams (mg) in divided doses per day. The doctor is the one who must adjust the dose according to the individual case.
  • Older adults. Initially, one to two mg in divided doses per day. The doctor can adjust the dose as needed.
  • Children under 12 years of age. Use and dosage should be determined by the doctor.

For oral tablet dosage form

  • From 12 years of age: Initially, two to three milligrams (mg) in divided doses per day.
  • Older adults. Initially, one to two mg in divided doses per day.
  • Children under 12 years. The doctor should determine the use and dose. 

Side effects

Any side effects of lorazepam usually occur at the beginning of treatment. Among these are the following:

Extremely frequent

  • Sedation.
  • Drowsiness.
  • Feelings of suffocation


  • Asthenia.
  • Muscular weakness.
  • Ataxia.
  • Confusion.
  • Depression.
  • Dizziness.
  • Fatigue.
  • Amnesia.
  • Disinhibition.
  • Irritability.
  • Changes in libido.
Woman with headache


  • Respiratory depression.
  • Respiratory insufficiency.
  • Seizures.
  • Dependence and abuse.
  • Tachycardia.
  • Hypotension.
  • Jaundice.
  • Cognitive deficit.
  • Changes in behaviors.

Lorazepam is a medicine that can only be prescribed by a qualified professional. In fact, it should never be self-medicated. This is due to the fact that it can have such powerful side effects.

If you’re taking this drug, stay on the prescribed dose, unless your doctor tells you otherwise. Furthermore, it’s extremely important that you visit your doctor for regular checks on your progress. In this way, they can assess if it’s working properly and make any necessary changes in its dosage.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.